diff --git a/Cargo.lock b/Cargo.lock
index 3d3706fc8..707855415 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1545,6 +1545,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "78c8292055d1c1df0cce5d180393dc8cce0abec0a7102adb6c7b1eef6016d60a"
 dependencies = [
  "generic-array 0.14.7",
+ "rand_core 0.6.4",
  "typenum",
 ]
 
@@ -1833,7 +1834,9 @@ dependencies = [
 name = "dbx-core"
 version = "0.1.0"
 dependencies = [
+ "aes-gcm 0.10.3",
  "anyhow",
+ "argon2",
  "async-trait",
  "base64 0.22.1",
  "bytes",
@@ -1860,6 +1863,7 @@ dependencies = [
  "rustls 0.23.40",
  "serde",
  "serde_json",
+ "sha2 0.10.9",
  "sqlparser",
  "tiberius",
  "tokio",
diff --git a/apps/desktop/src/components/editor/EditorSettingsDialog.vue b/apps/desktop/src/components/editor/EditorSettingsDialog.vue
index 25f50e827..e48e66ae0 100644
--- a/apps/desktop/src/components/editor/EditorSettingsDialog.vue
+++ b/apps/desktop/src/components/editor/EditorSettingsDialog.vue
@@ -1,8 +1,20 @@
 <script setup lang="ts">
-import { ref, watch, shallowRef, computed } from "vue";
+import { ref, watch, shallowRef, computed, onMounted } from "vue";
 import type { EditorView as EditorViewType } from "@codemirror/view";
 import { useI18n } from "vue-i18n";
-import { CircleHelp, ExternalLink, Loader2, Pencil, RefreshCw, Settings, Trash2 } from "lucide-vue-next";
+import {
+  CircleHelp,
+  Cloud,
+  Download,
+  ExternalLink,
+  Loader2,
+  Pencil,
+  RefreshCw,
+  Settings,
+  Trash2,
+  Upload,
+  X,
+} from "lucide-vue-next";
 import { Badge } from "@/components/ui/badge";
 import { Button } from "@/components/ui/button";
 import { Dialog, DialogContent, DialogFooter, DialogHeader, DialogTitle } from "@/components/ui/dialog";
@@ -13,6 +25,7 @@ import { Popover, PopoverContent, PopoverTrigger } from "@/components/ui/popover
 import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from "@/components/ui/select";
 import { Separator } from "@/components/ui/separator";
 import { Switch } from "@/components/ui/switch";
+import { Tooltip, TooltipContent, TooltipTrigger } from "@/components/ui/tooltip";
 import {
   useSettingsStore,
   AI_PROVIDER_PRESETS,
@@ -27,7 +40,19 @@ import {
 import { loadEditorTheme, editorFontTheme } from "@/lib/editorThemes";
 import { isTauriRuntime } from "@/lib/tauriRuntime";
 import { useTheme } from "@/composables/useTheme";
-import { aiListModels, aiTestConnection, listSystemFonts, type AiModelInfo } from "@/lib/api";
+import {
+  aiListModels,
+  aiTestConnection,
+  forgetWebdavSavedPassword,
+  listSystemFonts,
+  saveWebdavSavedPassword,
+  webdavPasswordStatus,
+  webdavSyncDownload,
+  webdavSyncTest,
+  webdavSyncUpload,
+  type AiModelInfo,
+  type WebDavConfig,
+} from "@/lib/api";
 import { eventToShortcut } from "@/lib/keyboardShortcuts";
 import {
   SHORTCUT_DEFINITIONS,
@@ -42,9 +67,11 @@ import { uuid } from "@/lib/utils";
 import { DEFAULT_SQL_SNIPPETS } from "@/lib/sqlCompletion";
 import AiProviderLogo from "@/components/icons/AiProviderLogo.vue";
 import type { AppThemeAppearance } from "@/lib/appTheme";
+import { useConnectionStore } from "@/stores/connectionStore";
 
 const { t } = useI18n();
 const settingsStore = useSettingsStore();
+const connectionStore = useConnectionStore();
 const { isDark } = useTheme();
 
 const props = defineProps<{
@@ -142,10 +169,6 @@ function confirmDeleteSnippet(snippet: SqlSnippet) {
   }
 }
 
-function restoreDefaultSnippets() {
-  editSnippets.value = DEFAULT_SQL_SNIPPETS.map((s) => ({ ...s }));
-}
-
 const presetFontLabels = new Map(FONT_FAMILIES.map((font) => [font.value, font.label]));
 
 function cssFontFamilyForName(name: string): string {
@@ -212,6 +235,7 @@ watch(
       void loadSystemFontOptions();
     }
   },
+  { immediate: true },
 );
 
 watch(
@@ -356,6 +380,7 @@ type SettingsCategory =
   | "redis"
   | "shortcuts"
   | "snippets"
+  | "sync"
   | "ai"
   | "security"
   | "about";
@@ -366,6 +391,7 @@ const settingsCategoryNav = computed<{ value: SettingsCategory; label: string }[
   { value: "redis", label: t("settings.redisTab") },
   { value: "shortcuts", label: t("settings.shortcutsTab") },
   { value: "snippets", label: t("settings.snippetsTab") },
+  ...(isWeb ? [] : [{ value: "sync" as const, label: t("settings.syncTab") }]),
   { value: "ai", label: t("settings.aiTab") },
   ...(isWeb ? [{ value: "security" as const, label: t("settings.securityTab") }] : []),
   { value: "about", label: t("settings.aboutTab") },
@@ -400,6 +426,138 @@ function openExternalUrl(url: string) {
   }
 }
 
+// ---------- WebDAV Sync ----------
+const webdavEndpoint = ref(localStorage.getItem("dbx-webdav-endpoint") || "");
+const webdavUsername = ref(localStorage.getItem("dbx-webdav-username") || "");
+const webdavPassword = ref("");
+const webdavRememberPassword = ref(localStorage.getItem("dbx-webdav-remember-password") === "true");
+const webdavHasSavedPassword = ref(false);
+const webdavRemotePath = ref(localStorage.getItem("dbx-webdav-remote-path") || "DBX/sync/snapshot.json");
+const webdavSyncSecrets = ref(false);
+const webdavSecretsPassphrase = ref("");
+const webdavBusy = ref<"" | "test" | "upload" | "download">("");
+const webdavMessage = ref("");
+const webdavError = ref(false);
+
+const webdavReady = computed(
+  () =>
+    !!webdavEndpoint.value.trim() &&
+    !webdavBusy.value &&
+    (!webdavSyncSecrets.value || !!webdavSecretsPassphrase.value.trim()),
+);
+
+function currentWebDavConfig(): WebDavConfig {
+  return {
+    endpoint: webdavEndpoint.value.trim(),
+    username: webdavUsername.value.trim() || undefined,
+    password: webdavPassword.value || undefined,
+    remotePath: webdavRemotePath.value.trim() || "DBX/sync/snapshot.json",
+  };
+}
+
+function currentWebDavAccountConfig(): WebDavConfig {
+  const config = currentWebDavConfig();
+  return { ...config, password: undefined };
+}
+
+function rememberWebDavFields() {
+  localStorage.setItem("dbx-webdav-endpoint", webdavEndpoint.value.trim());
+  localStorage.setItem("dbx-webdav-username", webdavUsername.value.trim());
+  localStorage.setItem("dbx-webdav-remote-path", webdavRemotePath.value.trim() || "DBX/sync/snapshot.json");
+}
+
+function setWebDavResult(message: string, error = false) {
+  webdavMessage.value = message;
+  webdavError.value = error;
+}
+
+async function runWebDavAction(kind: "test" | "upload" | "download", action: () => Promise<string>) {
+  webdavBusy.value = kind;
+  webdavMessage.value = "";
+  webdavError.value = false;
+  try {
+    rememberWebDavFields();
+    await applyWebDavPasswordPreference();
+    setWebDavResult(await action());
+  } catch (e: any) {
+    setWebDavResult(e?.message || String(e), true);
+  } finally {
+    webdavBusy.value = "";
+  }
+}
+
+async function refreshWebDavPasswordStatus() {
+  if (!webdavEndpoint.value.trim()) {
+    webdavHasSavedPassword.value = false;
+    webdavRememberPassword.value = false;
+    return;
+  }
+  try {
+    const status = await webdavPasswordStatus(currentWebDavAccountConfig());
+    webdavHasSavedPassword.value = status.hasSavedPassword;
+    if (status.hasSavedPassword) webdavRememberPassword.value = true;
+  } catch {
+    webdavHasSavedPassword.value = false;
+  }
+}
+
+async function applyWebDavPasswordPreference() {
+  const password = webdavPassword.value;
+  if (webdavRememberPassword.value && password) {
+    await saveWebdavSavedPassword(currentWebDavAccountConfig(), password);
+    webdavHasSavedPassword.value = true;
+    return;
+  }
+  if (!webdavRememberPassword.value && webdavHasSavedPassword.value) {
+    await forgetWebdavSavedPassword(currentWebDavAccountConfig());
+    webdavHasSavedPassword.value = false;
+  }
+}
+
+async function testWebDav() {
+  await runWebDavAction("test", async () => {
+    await webdavSyncTest(currentWebDavConfig());
+    return t("settings.syncTestSuccess");
+  });
+}
+
+async function uploadWebDavSnapshot() {
+  await runWebDavAction("upload", async () => {
+    const summary = await webdavSyncUpload(
+      currentWebDavConfig(),
+      settingsStore.editorSettings,
+      webdavSyncSecrets.value ? webdavSecretsPassphrase.value : undefined,
+    );
+    return t("settings.syncUploadSuccess", { bytes: summary.bytes, path: summary.remotePath });
+  });
+}
+
+async function downloadWebDavSnapshot() {
+  if (!window.confirm(t("settings.syncDownloadConfirm"))) return;
+  await runWebDavAction("download", async () => {
+    const result = await webdavSyncDownload(
+      currentWebDavConfig(),
+      webdavSyncSecrets.value ? webdavSecretsPassphrase.value : undefined,
+    );
+    if (result.editorSettings && typeof result.editorSettings === "object") {
+      settingsStore.updateEditorSettings(result.editorSettings as any);
+    }
+    await settingsStore.updateDesktopSettings(result.desktopSettings);
+    await connectionStore.initFromDisk();
+    const message = t("settings.syncDownloadSuccess", {
+      bytes: result.summary.bytes,
+      path: result.summary.remotePath,
+    });
+    if (result.applySummary.encryptedSecretsPresent && !result.applySummary.secretsApplied) {
+      return `${message} ${t("settings.syncSecretsSkipped")}`;
+    }
+    if (result.applySummary.secretsApplied) {
+      return `${message} ${t("settings.syncSecretsApplied")}`;
+    }
+    return message;
+  });
+}
+
 watch(
   () => props.open,
   async (open) => {
@@ -412,10 +570,25 @@ watch(
       await settingsStore.initAiConfig();
       await settingsStore.initDesktopSettings();
       editShowTrayIcon.value = settingsStore.desktopSettings.show_tray_icon;
+      webdavPassword.value = "";
+      await refreshWebDavPasswordStatus();
       syncAiEditState();
     }
   },
+  { immediate: true },
 );
+
+watch([webdavEndpoint, webdavUsername], () => {
+  void refreshWebDavPasswordStatus();
+});
+watch(webdavRememberPassword, (val) => {
+  localStorage.setItem("dbx-webdav-remember-password", String(val));
+});
+
+onMounted(() => {
+  void refreshWebDavPasswordStatus();
+});
+
 const oldPassword = ref("");
 const newPassword = ref("");
 const confirmNewPassword = ref("");
@@ -1040,11 +1213,16 @@ watch(
                 </div>
               </div>
               <div class="flex items-center justify-between gap-4 rounded-md border bg-muted/20 px-3 py-2">
-                <div class="space-y-1">
+                <div class="flex items-center gap-2">
                   <Label for="auto-select-active-sidebar-node">{{ t("settings.autoSelectActiveSidebarNode") }}</Label>
-                  <p class="text-xs text-muted-foreground">
-                    {{ t("settings.autoSelectActiveSidebarNodeDescription") }}
-                  </p>
+                  <Tooltip>
+                    <TooltipTrigger as-child>
+                      <CircleHelp class="h-3.5 w-3.5 cursor-help text-muted-foreground hover:text-foreground" />
+                    </TooltipTrigger>
+                    <TooltipContent class="max-w-[320px] text-xs leading-relaxed" side="top" align="start">
+                      {{ t("settings.autoSelectActiveSidebarNodeDescription") }}
+                    </TooltipContent>
+                  </Tooltip>
                 </div>
                 <Switch id="auto-select-active-sidebar-node" v-model="editAutoSelectActiveSidebarNode" />
               </div>
@@ -1168,11 +1346,103 @@ watch(
                   </tbody>
                 </table>
               </div>
+            </section>
 
-              <div class="flex justify-end">
-                <Button variant="outline" size="sm" @click="restoreDefaultSnippets">
-                  {{ t("settings.snippetsRestoreDefaults") }}
-                </Button>
+            <section v-else-if="activeSettingsTab === 'sync'" class="flex flex-col gap-5 py-2">
+              <div class="space-y-1">
+                <div class="flex items-center gap-2 text-sm font-medium">
+                  <Cloud class="h-4 w-4 text-muted-foreground" />
+                  {{ t("settings.syncWebDavTitle") }}
+                </div>
+                <p class="text-xs text-muted-foreground">{{ t("settings.syncWebDavDescription") }}</p>
+              </div>
+
+              <div class="grid gap-4 md:grid-cols-2">
+                <div class="space-y-2 md:col-span-2">
+                  <Label for="webdav-endpoint">{{ t("settings.syncEndpoint") }}</Label>
+                  <Input
+                    id="webdav-endpoint"
+                    v-model="webdavEndpoint"
+                    autocomplete="off"
+                    placeholder="https://example.com/remote.php/dav/files/user/"
+                  />
+                </div>
+                <div class="space-y-2">
+                  <Label for="webdav-username">{{ t("settings.syncUsername") }}</Label>
+                  <Input id="webdav-username" v-model="webdavUsername" autocomplete="username" />
+                </div>
+                <div class="space-y-2">
+                  <Label for="webdav-password">{{ t("settings.syncPassword") }}</Label>
+                  <div class="relative">
+                    <Input
+                      id="webdav-password"
+                      v-model="webdavPassword"
+                      type="password"
+                      :placeholder="webdavHasSavedPassword ? '••••••••' : '输入密码'"
+                      :disabled="webdavHasSavedPassword"
+                      autocomplete="current-password"
+                    />
+                    <Button
+                      v-if="webdavHasSavedPassword"
+                      variant="ghost"
+                      size="icon-xs"
+                      class="absolute right-1 top-1/2 -translate-y-1/2"
+                      title="清除已保存的密码"
+                      @click="
+                        webdavRememberPassword = false;
+                        forgetWebdavSavedPassword(currentWebDavAccountConfig());
+                        webdavHasSavedPassword = false;
+                        webdavPassword = '';
+                      "
+                    >
+                      <X class="size-3.5" />
+                    </Button>
+                  </div>
+                  <label class="flex items-center gap-2 text-xs text-muted-foreground">
+                    <input v-model="webdavRememberPassword" type="checkbox" class="h-4 w-4 shrink-0 accent-primary" />
+                    <span>
+                      {{ t("settings.syncRememberWebDavPassword") }}
+                      <span v-if="webdavHasSavedPassword">{{ t("settings.syncSavedPassword") }}</span>
+                    </span>
+                    <Tooltip>
+                      <TooltipTrigger as-child>
+                        <CircleHelp class="h-3.5 w-3.5 cursor-help text-muted-foreground hover:text-foreground" />
+                      </TooltipTrigger>
+                      <TooltipContent class="max-w-[320px] text-xs leading-relaxed" side="top" align="start">
+                        {{ t("settings.syncRememberWebDavPasswordDescription") }}
+                      </TooltipContent>
+                    </Tooltip>
+                  </label>
+                </div>
+                <div class="space-y-2 md:col-span-2">
+                  <Label for="webdav-remote-path">{{ t("settings.syncRemotePath") }}</Label>
+                  <Input id="webdav-remote-path" v-model="webdavRemotePath" autocomplete="off" />
+                  <p class="text-xs text-muted-foreground">{{ t("settings.syncRemotePathDescription") }}</p>
+                </div>
+              </div>
+
+              <div class="rounded-md border bg-muted/20 px-3 py-2 text-xs text-muted-foreground">
+                {{ t("settings.syncSecretNotice") }}
+              </div>
+
+              <div class="space-y-3 rounded-md border bg-muted/20 px-3 py-3">
+                <div class="flex items-center justify-between gap-4">
+                  <div class="space-y-1">
+                    <Label for="webdav-sync-secrets">{{ t("settings.syncSecrets") }}</Label>
+                    <p class="text-xs text-muted-foreground">{{ t("settings.syncSecretsDescription") }}</p>
+                  </div>
+                  <Switch id="webdav-sync-secrets" v-model="webdavSyncSecrets" />
+                </div>
+                <div v-if="webdavSyncSecrets" class="space-y-2">
+                  <Label for="webdav-secrets-passphrase">{{ t("settings.syncSecretsPassphrase") }}</Label>
+                  <Input
+                    id="webdav-secrets-passphrase"
+                    v-model="webdavSecretsPassphrase"
+                    type="password"
+                    autocomplete="new-password"
+                  />
+                  <p class="text-xs text-muted-foreground">{{ t("settings.syncSecretsPassphraseDescription") }}</p>
+                </div>
               </div>
             </section>
 
@@ -1532,6 +1802,37 @@ watch(
             <Button :disabled="!aiHasChanges()" @click="aiApplySettings">{{ t("settings.apply") }}</Button>
           </DialogFooter>
 
+          <DialogFooter
+            v-else-if="activeSettingsTab === 'sync'"
+            class="mx-0 mb-0 shrink-0 rounded-none border-t border-border/60 bg-transparent px-0 pb-0 pt-3 gap-3 sm:gap-3"
+          >
+            <Button variant="outline" @click="emit('update:open', false)">
+              {{ t("common.close") }}
+            </Button>
+            <p
+              v-if="webdavMessage"
+              class="text-xs self-center truncate max-w-[280px]"
+              :class="webdavError ? 'text-destructive' : 'text-green-500'"
+            >
+              {{ webdavMessage }}
+            </p>
+            <div class="flex-1" />
+            <Button variant="outline" :disabled="!webdavReady" @click="testWebDav">
+              <Loader2 v-if="webdavBusy === 'test'" class="mr-1 h-3 w-3 animate-spin" />
+              {{ t("settings.syncTest") }}
+            </Button>
+            <Button variant="outline" :disabled="!webdavReady" @click="downloadWebDavSnapshot">
+              <Loader2 v-if="webdavBusy === 'download'" class="mr-1 h-3 w-3 animate-spin" />
+              <Download v-else class="mr-1 h-3 w-3" />
+              {{ t("settings.syncDownload") }}
+            </Button>
+            <Button :disabled="!webdavReady" @click="uploadWebDavSnapshot">
+              <Loader2 v-if="webdavBusy === 'upload'" class="mr-1 h-3 w-3 animate-spin" />
+              <Upload v-else class="mr-1 h-3 w-3" />
+              {{ t("settings.syncUpload") }}
+            </Button>
+          </DialogFooter>
+
           <DialogFooter
             v-else-if="activeSettingsTab === 'security' && isWeb"
             class="mx-0 mb-0 shrink-0 rounded-none border-t border-border/60 bg-transparent px-0 pb-0 pt-3"
diff --git a/apps/desktop/src/i18n/locales/en.ts b/apps/desktop/src/i18n/locales/en.ts
index 0dc233618..0404a122d 100644
--- a/apps/desktop/src/i18n/locales/en.ts
+++ b/apps/desktop/src/i18n/locales/en.ts
@@ -1317,6 +1317,7 @@ export default {
     redisTab: "Redis",
     shortcutsTab: "Shortcuts",
     snippetsTab: "Snippets",
+    syncTab: "Sync",
     aiTab: "AI",
     jdbcTab: "JDBC Drivers",
     securityTab: "Security",
@@ -1368,6 +1369,34 @@ export default {
     snippetsRestoreDefaults: "Restore Defaults",
     snippetsAddTitle: "Add Snippet",
     snippetsEditTitle: "Edit Snippet",
+    syncWebDavTitle: "WebDAV Sync",
+    syncWebDavDescription: "Upload or restore a DBX snapshot from a WebDAV-compatible storage service.",
+    syncEndpoint: "WebDAV URL",
+    syncUsername: "Username",
+    syncPassword: "Password",
+    syncRememberWebDavPassword: "Remember WebDAV app password",
+    syncSavedPassword: "(saved)",
+    syncRememberWebDavPasswordDescription:
+      "The password is encrypted and stored on this device only. It is not synced to WebDAV and does not replace the sync password.",
+    syncRemotePath: "Remote snapshot path",
+    syncRemotePathDescription: "DBX will create missing parent folders when uploading.",
+    syncSecretNotice:
+      "By default, DBX syncs connection details and settings only. Database passwords, SSH passwords, proxy passwords, connection strings, and AI API keys stay local.",
+    syncSecrets: "Sync encrypted secrets",
+    syncSecretsDescription:
+      "When enabled, DBX encrypts database passwords, SSH passwords, and AI API keys before uploading them to WebDAV.",
+    syncSecretsPassphrase: "Sync password",
+    syncSecretsPassphraseDescription:
+      "This password is only used to encrypt and restore sensitive data. DBX does not save it; enter it again on each device.",
+    syncTest: "Test",
+    syncUpload: "Upload",
+    syncDownload: "Download",
+    syncTestSuccess: "WebDAV target is reachable.",
+    syncUploadSuccess: "Uploaded {bytes} bytes to {path}.",
+    syncDownloadSuccess: "Downloaded and applied {bytes} bytes from {path}.",
+    syncSecretsApplied: "Encrypted secrets were restored.",
+    syncSecretsSkipped: "Encrypted secrets were present but were not restored.",
+    syncDownloadConfirm: "Download and apply the remote DBX snapshot? Local metadata and saved SQL will be replaced.",
     apply: "Apply",
     reset: "Reset",
     resetDefaults: "Reset Defaults",
diff --git a/apps/desktop/src/i18n/locales/es.ts b/apps/desktop/src/i18n/locales/es.ts
index 8d41a13d9..0be15cad3 100644
--- a/apps/desktop/src/i18n/locales/es.ts
+++ b/apps/desktop/src/i18n/locales/es.ts
@@ -1212,6 +1212,8 @@ export default {
     navigationTab: "Navegación",
     redisTab: "Redis",
     shortcutsTab: "Atajos",
+    snippetsTab: "Fragmentos",
+    syncTab: "Sync",
     aiTab: "IA",
     jdbcTab: "Drivers JDBC",
     securityTab: "Seguridad",
@@ -1252,6 +1254,46 @@ export default {
     sidebarHiddenTablePrefixesDescription:
       "Un prefijo por linea. Solo acorta etiquetas de tablas, vistas y colecciones en la barra lateral; las acciones y ayudas usan el nombre completo.",
     sidebarHiddenTablePrefixesPlaceholder: "Ejemplo:\nODS_\nT8Y2_LONG_",
+    snippetsDescription: "Personaliza plantillas SQL activadas en el editor.",
+    snippetsAdd: "Agregar fragmento",
+    snippetsLabel: "Etiqueta",
+    snippetsPrefix: "Prefijo",
+    snippetsBody: "SQL",
+    snippetsLabelPlaceholder: "p. ej. select *",
+    snippetsPrefixPlaceholder: "p. ej. sel",
+    snippetsBodyPlaceholder: "SELECT *\nFROM table\nLIMIT 100;",
+    snippetsRestoreDefaults: "Restaurar valores por defecto",
+    snippetsAddTitle: "Agregar fragmento",
+    snippetsEditTitle: "Editar fragmento",
+    syncWebDavTitle: "Sincronización WebDAV",
+    syncWebDavDescription: "Sube o restaura una instantánea de DBX desde almacenamiento compatible con WebDAV.",
+    syncEndpoint: "URL WebDAV",
+    syncUsername: "Usuario",
+    syncPassword: "Contraseña",
+    syncRememberWebDavPassword: "Recordar contraseña de app WebDAV",
+    syncSavedPassword: "(guardada)",
+    syncRememberWebDavPasswordDescription:
+      "La contraseña se cifra y se guarda solo en este dispositivo. No se sincroniza a WebDAV ni reemplaza la contraseña de sync.",
+    syncRemotePath: "Ruta remota",
+    syncRemotePathDescription: "DBX creará las carpetas padre faltantes al subir.",
+    syncSecretNotice:
+      "De forma predeterminada, DBX solo sincroniza detalles de conexión y ajustes. Las contraseñas de base de datos, SSH, proxy, cadenas de conexión y API keys de IA quedan locales.",
+    syncSecrets: "Sincronizar secretos cifrados",
+    syncSecretsDescription:
+      "Al activarlo, DBX cifra contraseñas de base de datos, contraseñas SSH y API keys de IA antes de subirlas a WebDAV.",
+    syncSecretsPassphrase: "Contraseña de sync",
+    syncSecretsPassphraseDescription:
+      "Esta contraseña solo se usa para cifrar y restaurar datos sensibles. DBX no la guarda; tendrás que ingresarla en cada dispositivo.",
+    syncTest: "Probar",
+    syncUpload: "Subir",
+    syncDownload: "Descargar",
+    syncTestSuccess: "El destino WebDAV está disponible.",
+    syncUploadSuccess: "Se subieron {bytes} bytes a {path}.",
+    syncDownloadSuccess: "Se descargaron y aplicaron {bytes} bytes desde {path}.",
+    syncSecretsApplied: "Los secretos cifrados fueron restaurados.",
+    syncSecretsSkipped: "Había secretos cifrados, pero no fueron restaurados.",
+    syncDownloadConfirm:
+      "¿Descargar y aplicar la instantánea remota de DBX? Se reemplazarán metadatos locales y SQL guardado.",
     apply: "Aplicar",
     reset: "Restablecer",
     resetDefaults: "Restablecer valores por defecto",
diff --git a/apps/desktop/src/i18n/locales/zh-CN.ts b/apps/desktop/src/i18n/locales/zh-CN.ts
index bac4e1ddc..4c008a113 100644
--- a/apps/desktop/src/i18n/locales/zh-CN.ts
+++ b/apps/desktop/src/i18n/locales/zh-CN.ts
@@ -1294,6 +1294,7 @@ export default {
     redisTab: "Redis",
     shortcutsTab: "快捷键",
     snippetsTab: "代码片段",
+    syncTab: "同步",
     aiTab: "AI",
     jdbcTab: "JDBC 驱动",
     securityTab: "安全",
@@ -1342,6 +1343,30 @@ export default {
     snippetsRestoreDefaults: "恢复默认",
     snippetsAddTitle: "添加片段",
     snippetsEditTitle: "编辑片段",
+    syncWebDavTitle: "WebDAV 同步",
+    syncWebDavDescription: "将 DBX 快照上传到兼容 WebDAV 的存储服务，或从远端恢复。",
+    syncEndpoint: "WebDAV 地址",
+    syncUsername: "用户名",
+    syncPassword: "密码",
+    syncRememberWebDavPassword: "记住 WebDAV 应用密码",
+    syncSavedPassword: "（已保存）",
+    syncRememberWebDavPasswordDescription: "密码会加密保存在本机，不会同步到 WebDAV，也不会替代同步密码。",
+    syncRemotePath: "远端快照路径",
+    syncRemotePathDescription: "上传时 DBX 会自动创建缺失的父目录。",
+    syncSecretNotice: "默认只同步连接信息和设置，不会同步数据库密码、SSH 密码、代理密码、连接串或 AI API Key。",
+    syncSecrets: "同步加密后的敏感信息",
+    syncSecretsDescription: "开启后，DBX 会先加密数据库密码、SSH 密码和 AI API Key，再上传到 WebDAV。",
+    syncSecretsPassphrase: "同步密码",
+    syncSecretsPassphraseDescription: "这个密码只用于加密和恢复敏感信息，DBX 不会保存；换设备恢复时需要再次输入。",
+    syncTest: "测试",
+    syncUpload: "上传",
+    syncDownload: "下载",
+    syncTestSuccess: "WebDAV 目标可访问。",
+    syncUploadSuccess: "已上传 {bytes} 字节到 {path}。",
+    syncDownloadSuccess: "已从 {path} 下载并应用 {bytes} 字节。",
+    syncSecretsApplied: "已恢复加密敏感信息。",
+    syncSecretsSkipped: "远端包含加密敏感信息，但本次未恢复。",
+    syncDownloadConfirm: "要下载并应用远端 DBX 快照吗？本地元信息和保存的 SQL 会被替换。",
     apply: "应用",
     reset: "重置",
     resetDefaults: "恢复默认",
diff --git a/apps/desktop/src/lib/api.ts b/apps/desktop/src/lib/api.ts
index 4613afc12..77c6fe486 100644
--- a/apps/desktop/src/lib/api.ts
+++ b/apps/desktop/src/lib/api.ts
@@ -142,6 +142,12 @@ export const loadDesktopSettings = forward("loadDesktopSettings");
 export const saveDesktopSettings = forward("saveDesktopSettings");
 export const loadPinnedTreeNodeIds = forward("loadPinnedTreeNodeIds");
 export const savePinnedTreeNodeIds = forward("savePinnedTreeNodeIds");
+export const webdavSyncTest = forward("webdavSyncTest");
+export const webdavPasswordStatus = forward("webdavPasswordStatus");
+export const saveWebdavSavedPassword = forward("saveWebdavSavedPassword");
+export const forgetWebdavSavedPassword = forward("forgetWebdavSavedPassword");
+export const webdavSyncUpload = forward("webdavSyncUpload");
+export const webdavSyncDownload = forward("webdavSyncDownload");
 export const saveAiConversation = forward("saveAiConversation");
 export const loadAiConversations = forward("loadAiConversations");
 export const deleteAiConversation = forward("deleteAiConversation");
@@ -237,6 +243,10 @@ export type {
   JavaRuntimeMode,
   JavaRuntimeConfig,
   DriverInstallProgress,
+  WebDavConfig,
+  WebDavPasswordStatus,
+  WebDavSyncSummary,
+  WebDavDownloadResult,
   UpdateInfo,
   RedisDatabaseInfo,
   RedisKeyInfo,
diff --git a/apps/desktop/src/lib/http.ts b/apps/desktop/src/lib/http.ts
index 249588675..2a107d9b7 100644
--- a/apps/desktop/src/lib/http.ts
+++ b/apps/desktop/src/lib/http.ts
@@ -776,6 +776,65 @@ export async function saveDesktopSettings(_settings: DesktopSettings): Promise<v
   return;
 }
 
+export interface WebDavConfig {
+  endpoint: string;
+  username?: string;
+  password?: string;
+  remotePath?: string;
+}
+
+export interface WebDavSyncSummary {
+  remotePath: string;
+  bytes: number;
+  exportedAt?: string;
+  appVersion?: string;
+}
+
+export interface WebDavDownloadResult {
+  summary: WebDavSyncSummary;
+  editorSettings?: unknown;
+  desktopSettings: DesktopSettings;
+  applySummary: {
+    encryptedSecretsPresent: boolean;
+    secretsApplied: boolean;
+  };
+}
+
+export interface WebDavPasswordStatus {
+  hasSavedPassword: boolean;
+}
+
+export async function webdavSyncTest(_config: WebDavConfig): Promise<void> {
+  throw new Error("WebDAV sync is only available in the desktop app.");
+}
+
+export async function webdavPasswordStatus(_config: WebDavConfig): Promise<WebDavPasswordStatus> {
+  return { hasSavedPassword: false };
+}
+
+export async function saveWebdavSavedPassword(_config: WebDavConfig, _password: string): Promise<void> {
+  throw new Error("WebDAV sync is only available in the desktop app.");
+}
+
+export async function forgetWebdavSavedPassword(_config: WebDavConfig): Promise<void> {
+  throw new Error("WebDAV sync is only available in the desktop app.");
+}
+
+export async function webdavSyncUpload(
+  _config: WebDavConfig,
+  _editorSettings?: unknown,
+  _secretsPassphrase?: string,
+): Promise<WebDavSyncSummary> {
+  throw new Error("WebDAV sync is only available in the desktop app.");
+}
+
+export async function webdavSyncDownload(
+  _config: WebDavConfig,
+  _secretsPassphrase?: string,
+): Promise<WebDavDownloadResult> {
+  throw new Error("WebDAV sync is only available in the desktop app.");
+}
+
 export async function loadPinnedTreeNodeIds(): Promise<string[]> {
   return get("/api/app-settings/pinned-tree-node-ids");
 }
diff --git a/apps/desktop/src/lib/tauri.ts b/apps/desktop/src/lib/tauri.ts
index acf55aa10..696b5a152 100644
--- a/apps/desktop/src/lib/tauri.ts
+++ b/apps/desktop/src/lib/tauri.ts
@@ -93,6 +93,34 @@ export interface DesktopSettings {
   show_tray_icon: boolean;
 }
 
+export interface WebDavConfig {
+  endpoint: string;
+  username?: string;
+  password?: string;
+  remotePath?: string;
+}
+
+export interface WebDavSyncSummary {
+  remotePath: string;
+  bytes: number;
+  exportedAt?: string;
+  appVersion?: string;
+}
+
+export interface WebDavDownloadResult {
+  summary: WebDavSyncSummary;
+  editorSettings?: unknown;
+  desktopSettings: DesktopSettings;
+  applySummary: {
+    encryptedSecretsPresent: boolean;
+    secretsApplied: boolean;
+  };
+}
+
+export interface WebDavPasswordStatus {
+  hasSavedPassword: boolean;
+}
+
 export interface QueryPagination {
   limit: number;
   offset: number;
@@ -236,6 +264,37 @@ export async function saveDesktopSettings(settings: DesktopSettings): Promise<vo
   return invoke("save_desktop_settings", { settings });
 }
 
+export async function webdavSyncTest(config: WebDavConfig): Promise<void> {
+  return invoke("webdav_sync_test", { config });
+}
+
+export async function webdavPasswordStatus(config: WebDavConfig): Promise<WebDavPasswordStatus> {
+  return invoke("webdav_password_status", { config });
+}
+
+export async function saveWebdavSavedPassword(config: WebDavConfig, password: string): Promise<void> {
+  return invoke("save_webdav_saved_password", { config, password });
+}
+
+export async function forgetWebdavSavedPassword(config: WebDavConfig): Promise<void> {
+  return invoke("forget_webdav_saved_password", { config });
+}
+
+export async function webdavSyncUpload(
+  config: WebDavConfig,
+  editorSettings?: unknown,
+  secretsPassphrase?: string,
+): Promise<WebDavSyncSummary> {
+  return invoke("webdav_sync_upload", { config, editorSettings, secretsPassphrase });
+}
+
+export async function webdavSyncDownload(
+  config: WebDavConfig,
+  secretsPassphrase?: string,
+): Promise<WebDavDownloadResult> {
+  return invoke("webdav_sync_download", { config, secretsPassphrase });
+}
+
 export async function loadPinnedTreeNodeIds(): Promise<string[]> {
   return invoke("load_pinned_tree_node_ids");
 }
diff --git a/crates/dbx-core/Cargo.toml b/crates/dbx-core/Cargo.toml
index 68a512af1..9efbf7172 100644
--- a/crates/dbx-core/Cargo.toml
+++ b/crates/dbx-core/Cargo.toml
@@ -40,6 +40,9 @@ portpicker = "0.1.1"
 csv = "1"
 calamine = "0.30.1"
 base64 = "0.22"
+aes-gcm = "0.10"
+argon2 = "0.5"
+sha2 = "0.10"
 async-trait = "0.1"
 bytes = "1"
 font-kit = "0.14.3"
diff --git a/crates/dbx-core/src/cloud_sync.rs b/crates/dbx-core/src/cloud_sync.rs
new file mode 100644
index 000000000..4171db9c1
--- /dev/null
+++ b/crates/dbx-core/src/cloud_sync.rs
@@ -0,0 +1,565 @@
+use aes_gcm::{
+    aead::{rand_core::RngCore, Aead, OsRng},
+    Aes256Gcm, KeyInit, Nonce,
+};
+use argon2::{Algorithm, Argon2, Params, Version};
+use base64::{engine::general_purpose::STANDARD as BASE64, engine::general_purpose::URL_SAFE_NO_PAD, Engine as _};
+use chrono::Utc;
+use reqwest::{header, Client, Method, StatusCode, Url};
+use serde::{Deserialize, Serialize};
+use sha2::{Digest, Sha256};
+
+use crate::ai::AiConfig;
+use crate::models::connection::ConnectionConfig;
+use crate::saved_sql::SavedSqlLibrary;
+use crate::storage::{DesktopSettings, Storage};
+
+const SNAPSHOT_SCHEMA_VERSION: u32 = 1;
+const DEFAULT_REMOTE_PATH: &str = "DBX/sync/snapshot.json";
+const SECRET_KEYS: &[&str] = &[
+    "password",
+    "ssh_password",
+    "ssh_key_passphrase",
+    "proxy_password",
+    "redis_sentinel_password",
+    "connection_string",
+];
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct WebDavConfig {
+    pub endpoint: String,
+    pub username: Option<String>,
+    pub password: Option<String>,
+    pub remote_path: Option<String>,
+}
+
+#[derive(Debug, Clone, Copy, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct WebDavPasswordStatus {
+    pub has_saved_password: bool,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct SyncSnapshot {
+    pub schema_version: u32,
+    pub exported_at: String,
+    pub app_version: String,
+    pub connections: Vec<ConnectionConfig>,
+    pub sidebar_layout: Option<serde_json::Value>,
+    pub pinned_tree_node_ids: Vec<String>,
+    pub saved_sql: SavedSqlLibrary,
+    pub desktop_settings: DesktopSettings,
+    pub editor_settings: Option<serde_json::Value>,
+    pub encrypted_secrets: Option<EncryptedSecretsBlob>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct EncryptedSecretsBlob {
+    pub version: u32,
+    pub kdf: String,
+    pub cipher: String,
+    pub salt: String,
+    pub nonce: String,
+    pub ciphertext: String,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct SensitiveSyncPayload {
+    pub connection_secrets: Vec<ConnectionSecretSnapshot>,
+    pub ai_config: Option<AiConfig>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ConnectionSecretSnapshot {
+    pub connection_id: String,
+    pub key: String,
+    pub secret: String,
+}
+
+#[derive(Debug, Clone, Copy, Default)]
+pub struct ApplySnapshotOptions<'a> {
+    pub secrets_passphrase: Option<&'a str>,
+}
+
+#[derive(Debug, Clone, Copy, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ApplySnapshotSummary {
+    pub encrypted_secrets_present: bool,
+    pub secrets_applied: bool,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct WebDavSyncSummary {
+    pub remote_path: String,
+    pub bytes: usize,
+    pub exported_at: Option<String>,
+    pub app_version: Option<String>,
+}
+
+pub async fn build_sync_snapshot(
+    storage: &Storage,
+    app_version: impl Into<String>,
+    editor_settings: Option<serde_json::Value>,
+    secrets_passphrase: Option<&str>,
+) -> Result<SyncSnapshot, String> {
+    let mut connections = storage.load_connections().await?;
+    let encrypted_secrets = match normalized_passphrase(secrets_passphrase) {
+        Some(passphrase) => {
+            Some(encrypt_sensitive_payload(&build_sensitive_payload(storage, &connections).await?, passphrase)?)
+        }
+        None => None,
+    };
+    for config in &mut connections {
+        scrub_connection_secrets(config);
+    }
+
+    Ok(SyncSnapshot {
+        schema_version: SNAPSHOT_SCHEMA_VERSION,
+        exported_at: Utc::now().to_rfc3339(),
+        app_version: app_version.into(),
+        connections,
+        sidebar_layout: storage.load_sidebar_layout().await?,
+        pinned_tree_node_ids: storage.load_pinned_tree_node_ids().await?,
+        saved_sql: storage.load_saved_sql_library().await?,
+        desktop_settings: storage.load_desktop_settings().await?,
+        editor_settings,
+        encrypted_secrets,
+    })
+}
+
+pub async fn apply_sync_snapshot(
+    storage: &Storage,
+    snapshot: &SyncSnapshot,
+    options: ApplySnapshotOptions<'_>,
+) -> Result<ApplySnapshotSummary, String> {
+    if snapshot.schema_version != SNAPSHOT_SCHEMA_VERSION {
+        return Err(format!("Unsupported sync snapshot schema version: {}", snapshot.schema_version));
+    }
+
+    let encrypted_secrets_present = snapshot.encrypted_secrets.is_some();
+    let sensitive_payload = match (&snapshot.encrypted_secrets, normalized_passphrase(options.secrets_passphrase)) {
+        (Some(blob), Some(passphrase)) => Some(decrypt_sensitive_payload(blob, passphrase)?),
+        _ => None,
+    };
+
+    let mut connections = snapshot.connections.clone();
+    for config in &mut connections {
+        scrub_connection_secrets(config);
+    }
+
+    storage.save_connection_metadata_preserving_secrets(&connections).await?;
+    if let Some(layout) = &snapshot.sidebar_layout {
+        storage.save_sidebar_layout(layout).await?;
+    }
+    storage.save_pinned_tree_node_ids(&snapshot.pinned_tree_node_ids).await?;
+    storage.replace_saved_sql_library(&snapshot.saved_sql).await?;
+    storage.save_desktop_settings(&snapshot.desktop_settings).await?;
+    if let Some(payload) = &sensitive_payload {
+        clear_connection_secrets(storage, &connections).await?;
+        apply_sensitive_payload(storage, payload).await?;
+    }
+    Ok(ApplySnapshotSummary { encrypted_secrets_present, secrets_applied: sensitive_payload.is_some() })
+}
+
+pub struct WebDavClient {
+    http: Client,
+    config: WebDavConfig,
+}
+
+pub async fn webdav_saved_password_status(
+    storage: &Storage,
+    config: &WebDavConfig,
+) -> Result<WebDavPasswordStatus, String> {
+    let account = webdav_password_account(config);
+    Ok(WebDavPasswordStatus { has_saved_password: storage.load_webdav_password_blob(&account).await?.is_some() })
+}
+
+pub async fn save_webdav_password(storage: &Storage, config: &WebDavConfig, password: &str) -> Result<(), String> {
+    let secret = storage.load_or_create_local_device_secret().await?;
+    let blob = encrypt_text_with_secret(password, &secret)?;
+    let value = serde_json::to_value(blob).map_err(|e| e.to_string())?;
+    storage.save_webdav_password_blob(&webdav_password_account(config), &value).await
+}
+
+pub async fn forget_webdav_password(storage: &Storage, config: &WebDavConfig) -> Result<(), String> {
+    storage.delete_webdav_password_blob(&webdav_password_account(config)).await
+}
+
+pub async fn resolve_webdav_password(storage: &Storage, config: &mut WebDavConfig) -> Result<(), String> {
+    if config.password.as_deref().is_some_and(|password| !password.is_empty()) {
+        return Ok(());
+    }
+    let Some(value) = storage.load_webdav_password_blob(&webdav_password_account(config)).await? else {
+        return Ok(());
+    };
+    let blob: EncryptedSecretsBlob = serde_json::from_value(value).map_err(|e| e.to_string())?;
+    let secret = storage.load_or_create_local_device_secret().await?;
+    config.password = Some(decrypt_text_with_secret(&blob, &secret)?);
+    Ok(())
+}
+
+impl WebDavClient {
+    pub fn new(config: WebDavConfig) -> Self {
+        Self { http: Client::new(), config }
+    }
+
+    pub fn remote_path(&self) -> String {
+        normalized_remote_path(self.config.remote_path.as_deref())
+    }
+
+    pub async fn test(&self) -> Result<(), String> {
+        let method = Method::from_bytes(b"PROPFIND").map_err(|e| e.to_string())?;
+        let response = self.request(method, "")?.header("Depth", "0").send().await.map_err(|e| e.to_string())?;
+        let status = response.status();
+        if status.is_success() {
+            Ok(())
+        } else {
+            Err(format!("WebDAV test failed with HTTP {status}"))
+        }
+    }
+
+    pub async fn put_snapshot(&self, snapshot: &SyncSnapshot) -> Result<WebDavSyncSummary, String> {
+        let remote_path = self.remote_path();
+        self.ensure_parent_collections(&remote_path).await?;
+        let bytes = serde_json::to_vec_pretty(snapshot).map_err(|e| e.to_string())?;
+        let response = self
+            .request(Method::PUT, &remote_path)?
+            .header(header::CONTENT_TYPE, "application/json")
+            .body(bytes.clone())
+            .send()
+            .await
+            .map_err(|e| e.to_string())?;
+        let status = response.status();
+        if !status.is_success() {
+            return Err(format!("WebDAV upload failed with HTTP {status}"));
+        }
+        Ok(WebDavSyncSummary {
+            remote_path,
+            bytes: bytes.len(),
+            exported_at: Some(snapshot.exported_at.clone()),
+            app_version: Some(snapshot.app_version.clone()),
+        })
+    }
+
+    pub async fn get_snapshot(&self) -> Result<(SyncSnapshot, WebDavSyncSummary), String> {
+        let remote_path = self.remote_path();
+        let response = self.request(Method::GET, &remote_path)?.send().await.map_err(|e| e.to_string())?;
+        let status = response.status();
+        if !status.is_success() {
+            return Err(format!("WebDAV download failed with HTTP {status}"));
+        }
+        let bytes = response.bytes().await.map_err(|e| e.to_string())?;
+        let snapshot: SyncSnapshot = serde_json::from_slice(&bytes).map_err(|e| e.to_string())?;
+        let summary = WebDavSyncSummary {
+            remote_path,
+            bytes: bytes.len(),
+            exported_at: Some(snapshot.exported_at.clone()),
+            app_version: Some(snapshot.app_version.clone()),
+        };
+        Ok((snapshot, summary))
+    }
+
+    async fn ensure_parent_collections(&self, remote_path: &str) -> Result<(), String> {
+        let method = Method::from_bytes(b"MKCOL").map_err(|e| e.to_string())?;
+        for parent in parent_collection_paths(remote_path) {
+            let response = self.request(method.clone(), &parent)?.send().await.map_err(|e| e.to_string())?;
+            let status = response.status();
+            if status.is_success() || status == StatusCode::METHOD_NOT_ALLOWED {
+                continue;
+            }
+            return Err(format!("Failed to create WebDAV collection '{parent}' with HTTP {status}"));
+        }
+        Ok(())
+    }
+
+    fn request(&self, method: Method, remote_path: &str) -> Result<reqwest::RequestBuilder, String> {
+        let url = self.remote_url(remote_path)?;
+        let mut request = self.http.request(method, url);
+        if let Some(username) = self.config.username.as_deref().filter(|value| !value.is_empty()) {
+            request = request.basic_auth(username, self.config.password.clone());
+        }
+        Ok(request)
+    }
+
+    fn remote_url(&self, remote_path: &str) -> Result<Url, String> {
+        let endpoint = self.config.endpoint.trim();
+        if endpoint.is_empty() {
+            return Err("WebDAV endpoint is required".to_string());
+        }
+        let base = if endpoint.ends_with('/') { endpoint.to_string() } else { format!("{endpoint}/") };
+        let base = Url::parse(&base).map_err(|e| e.to_string())?;
+        base.join(remote_path.trim_start_matches('/')).map_err(|e| e.to_string())
+    }
+}
+
+fn scrub_connection_secrets(config: &mut ConnectionConfig) {
+    config.password.clear();
+    config.ssh_password.clear();
+    config.ssh_key_passphrase.clear();
+    config.proxy_password.clear();
+    config.redis_sentinel_password.clear();
+    config.connection_string = None;
+}
+
+fn webdav_password_account(config: &WebDavConfig) -> String {
+    let mut hasher = Sha256::new();
+    hasher.update(config.endpoint.trim().as_bytes());
+    hasher.update(b"\n");
+    hasher.update(config.username.as_deref().unwrap_or("").trim().as_bytes());
+    URL_SAFE_NO_PAD.encode(hasher.finalize())
+}
+
+async fn build_sensitive_payload(
+    storage: &Storage,
+    connections: &[ConnectionConfig],
+) -> Result<SensitiveSyncPayload, String> {
+    let mut connection_secrets = Vec::new();
+    for config in connections {
+        push_secret(&mut connection_secrets, &config.id, "password", &config.password);
+        push_secret(&mut connection_secrets, &config.id, "ssh_password", &config.ssh_password);
+        push_secret(&mut connection_secrets, &config.id, "ssh_key_passphrase", &config.ssh_key_passphrase);
+        push_secret(&mut connection_secrets, &config.id, "proxy_password", &config.proxy_password);
+        push_secret(&mut connection_secrets, &config.id, "redis_sentinel_password", &config.redis_sentinel_password);
+        if let Some(connection_string) = &config.connection_string {
+            push_secret(&mut connection_secrets, &config.id, "connection_string", connection_string);
+        }
+    }
+
+    Ok(SensitiveSyncPayload { connection_secrets, ai_config: storage.load_ai_config().await? })
+}
+
+fn push_secret(secrets: &mut Vec<ConnectionSecretSnapshot>, connection_id: &str, key: &str, secret: &str) {
+    if secret.is_empty() {
+        return;
+    }
+    secrets.push(ConnectionSecretSnapshot {
+        connection_id: connection_id.to_string(),
+        key: key.to_string(),
+        secret: secret.to_string(),
+    });
+}
+
+async fn apply_sensitive_payload(storage: &Storage, payload: &SensitiveSyncPayload) -> Result<(), String> {
+    for secret in &payload.connection_secrets {
+        if !SECRET_KEYS.contains(&secret.key.as_str()) {
+            continue;
+        }
+        storage.set_secret(&secret.connection_id, &secret.key, &secret.secret).await?;
+    }
+    if let Some(ai_config) = &payload.ai_config {
+        storage.save_ai_config(ai_config).await?;
+    }
+    Ok(())
+}
+
+async fn clear_connection_secrets(storage: &Storage, connections: &[ConnectionConfig]) -> Result<(), String> {
+    for config in connections {
+        for key in SECRET_KEYS {
+            storage.delete_secret(&config.id, key).await?;
+        }
+    }
+    Ok(())
+}
+
+fn encrypt_sensitive_payload(payload: &SensitiveSyncPayload, passphrase: &str) -> Result<EncryptedSecretsBlob, String> {
+    let plaintext = serde_json::to_vec(payload).map_err(|e| e.to_string())?;
+    encrypt_bytes_with_secret(&plaintext, passphrase)
+}
+
+fn decrypt_sensitive_payload(blob: &EncryptedSecretsBlob, passphrase: &str) -> Result<SensitiveSyncPayload, String> {
+    let plaintext = decrypt_bytes_with_secret(blob, passphrase)
+        .map_err(|_| "Failed to decrypt synced secrets. Check the sync password.".to_string())?;
+    serde_json::from_slice(&plaintext).map_err(|e| e.to_string())
+}
+
+fn encrypt_text_with_secret(value: &str, secret: &str) -> Result<EncryptedSecretsBlob, String> {
+    encrypt_bytes_with_secret(value.as_bytes(), secret)
+}
+
+fn decrypt_text_with_secret(blob: &EncryptedSecretsBlob, secret: &str) -> Result<String, String> {
+    let plaintext = decrypt_bytes_with_secret(blob, secret)?;
+    String::from_utf8(plaintext).map_err(|e| e.to_string())
+}
+
+fn encrypt_bytes_with_secret(plaintext: &[u8], secret: &str) -> Result<EncryptedSecretsBlob, String> {
+    let mut salt = [0u8; 16];
+    let mut nonce = [0u8; 12];
+    OsRng.fill_bytes(&mut salt);
+    OsRng.fill_bytes(&mut nonce);
+    let key = derive_secret_key(secret, &salt)?;
+    let cipher = Aes256Gcm::new_from_slice(&key).map_err(|e| e.to_string())?;
+    let ciphertext = cipher.encrypt(Nonce::from_slice(&nonce), plaintext).map_err(|e| e.to_string())?;
+    Ok(EncryptedSecretsBlob {
+        version: 1,
+        kdf: "argon2id".to_string(),
+        cipher: "aes-256-gcm".to_string(),
+        salt: BASE64.encode(salt),
+        nonce: BASE64.encode(nonce),
+        ciphertext: BASE64.encode(ciphertext),
+    })
+}
+
+fn decrypt_bytes_with_secret(blob: &EncryptedSecretsBlob, secret: &str) -> Result<Vec<u8>, String> {
+    if blob.version != 1 || blob.kdf != "argon2id" || blob.cipher != "aes-256-gcm" {
+        return Err("Unsupported encrypted secrets format".to_string());
+    }
+    let salt = BASE64.decode(&blob.salt).map_err(|e| e.to_string())?;
+    let nonce = BASE64.decode(&blob.nonce).map_err(|e| e.to_string())?;
+    let ciphertext = BASE64.decode(&blob.ciphertext).map_err(|e| e.to_string())?;
+    if nonce.len() != 12 {
+        return Err("Invalid encrypted secrets nonce".to_string());
+    }
+    let key = derive_secret_key(secret, &salt)?;
+    let cipher = Aes256Gcm::new_from_slice(&key).map_err(|e| e.to_string())?;
+    cipher
+        .decrypt(Nonce::from_slice(&nonce), ciphertext.as_ref())
+        .map_err(|_| "Failed to decrypt saved secret.".to_string())
+}
+
+fn derive_secret_key(passphrase: &str, salt: &[u8]) -> Result<[u8; 32], String> {
+    let params = Params::new(19 * 1024, 2, 1, Some(32)).map_err(|e| e.to_string())?;
+    let argon2 = Argon2::new(Algorithm::Argon2id, Version::V0x13, params);
+    let mut key = [0u8; 32];
+    argon2.hash_password_into(passphrase.as_bytes(), salt, &mut key).map_err(|e| e.to_string())?;
+    Ok(key)
+}
+
+fn normalized_passphrase(passphrase: Option<&str>) -> Option<&str> {
+    passphrase.map(str::trim).filter(|value| !value.is_empty())
+}
+
+fn normalized_remote_path(value: Option<&str>) -> String {
+    let value = value.unwrap_or(DEFAULT_REMOTE_PATH).trim().trim_start_matches('/');
+    if value.is_empty() {
+        DEFAULT_REMOTE_PATH.to_string()
+    } else {
+        value.to_string()
+    }
+}
+
+fn parent_collection_paths(remote_path: &str) -> Vec<String> {
+    let parts = remote_path.trim_matches('/').split('/').filter(|part| !part.is_empty()).collect::<Vec<_>>();
+    if parts.len() <= 1 {
+        return Vec::new();
+    }
+
+    let mut paths = Vec::with_capacity(parts.len() - 1);
+    for index in 1..parts.len() {
+        paths.push(parts[..index].join("/"));
+    }
+    paths
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{
+        decrypt_sensitive_payload, encrypt_sensitive_payload, normalized_remote_path, parent_collection_paths,
+        scrub_connection_secrets, ConnectionSecretSnapshot, SensitiveSyncPayload,
+    };
+    use crate::models::connection::{ConnectionConfig, DatabaseType, ProxyType};
+
+    #[test]
+    fn normalizes_empty_remote_path_to_default() {
+        assert_eq!(normalized_remote_path(None), "DBX/sync/snapshot.json");
+        assert_eq!(normalized_remote_path(Some("")), "DBX/sync/snapshot.json");
+        assert_eq!(normalized_remote_path(Some("/custom/snapshot.json")), "custom/snapshot.json");
+    }
+
+    #[test]
+    fn returns_parent_collection_paths_from_leaf() {
+        assert_eq!(parent_collection_paths("dbx/sync/snapshot.json"), vec!["dbx".to_string(), "dbx/sync".to_string()]);
+    }
+
+    #[test]
+    fn scrubs_connection_secret_fields() {
+        let mut config = ConnectionConfig {
+            id: "id".to_string(),
+            name: "name".to_string(),
+            db_type: DatabaseType::Postgres,
+            driver_profile: None,
+            driver_label: None,
+            url_params: None,
+            host: "localhost".to_string(),
+            port: 5432,
+            username: "user".to_string(),
+            password: "secret".to_string(),
+            database: None,
+            visible_databases: None,
+            attached_databases: Vec::new(),
+            color: None,
+            ssh_enabled: false,
+            ssh_host: String::new(),
+            ssh_port: 22,
+            ssh_user: String::new(),
+            ssh_password: "ssh".to_string(),
+            ssh_key_path: String::new(),
+            ssh_key_passphrase: "key".to_string(),
+            ssh_expose_lan: false,
+            ssh_connect_timeout_secs: 5,
+            proxy_enabled: false,
+            proxy_type: ProxyType::Socks5,
+            proxy_host: String::new(),
+            proxy_port: 1080,
+            proxy_username: String::new(),
+            proxy_password: "proxy".to_string(),
+            ssl: false,
+            ca_cert_path: String::new(),
+            sysdba: false,
+            oracle_connection_type: None,
+            connection_string: Some("postgres://secret".to_string()),
+            redis_connection_mode: None,
+            redis_sentinel_master: String::new(),
+            redis_sentinel_nodes: String::new(),
+            redis_sentinel_username: String::new(),
+            redis_sentinel_password: "sentinel".to_string(),
+            redis_sentinel_tls: false,
+            external_config: None,
+            jdbc_driver_class: None,
+            jdbc_driver_paths: Vec::new(),
+            one_time: false,
+        };
+        scrub_connection_secrets(&mut config);
+        assert!(config.password.is_empty());
+        assert!(config.ssh_password.is_empty());
+        assert!(config.ssh_key_passphrase.is_empty());
+        assert!(config.proxy_password.is_empty());
+        assert!(config.redis_sentinel_password.is_empty());
+        assert!(config.connection_string.is_none());
+    }
+
+    #[test]
+    fn encrypted_sensitive_payload_round_trips() {
+        let payload = SensitiveSyncPayload {
+            connection_secrets: vec![ConnectionSecretSnapshot {
+                connection_id: "c1".to_string(),
+                key: "password".to_string(),
+                secret: "secret".to_string(),
+            }],
+            ai_config: None,
+        };
+        let encrypted = encrypt_sensitive_payload(&payload, "sync-pass").unwrap();
+        assert_ne!(encrypted.ciphertext, "secret");
+        let decrypted = decrypt_sensitive_payload(&encrypted, "sync-pass").unwrap();
+        assert_eq!(decrypted.connection_secrets[0].secret, "secret");
+    }
+
+    #[test]
+    fn encrypted_sensitive_payload_rejects_wrong_passphrase() {
+        let payload = SensitiveSyncPayload {
+            connection_secrets: vec![ConnectionSecretSnapshot {
+                connection_id: "c1".to_string(),
+                key: "password".to_string(),
+                secret: "secret".to_string(),
+            }],
+            ai_config: None,
+        };
+        let encrypted = encrypt_sensitive_payload(&payload, "sync-pass").unwrap();
+        assert!(decrypt_sensitive_payload(&encrypted, "wrong-pass").is_err());
+    }
+}
diff --git a/crates/dbx-core/src/lib.rs b/crates/dbx-core/src/lib.rs
index 4e3e2a3e8..8c7f6eb6f 100644
--- a/crates/dbx-core/src/lib.rs
+++ b/crates/dbx-core/src/lib.rs
@@ -1,6 +1,7 @@
 pub mod agent_manager;
 pub mod agent_service;
 pub mod ai;
+pub mod cloud_sync;
 pub mod connection;
 pub mod connection_secrets;
 pub mod csv_export;
diff --git a/crates/dbx-core/src/storage.rs b/crates/dbx-core/src/storage.rs
index 4e5daae7d..c24a234fa 100644
--- a/crates/dbx-core/src/storage.rs
+++ b/crates/dbx-core/src/storage.rs
@@ -3,6 +3,7 @@ use std::path::Path;
 
 use rusqlite::{params, params_from_iter, Connection, OptionalExtension, ToSql};
 use serde::{Deserialize, Serialize};
+use uuid::Uuid;
 
 use crate::ai::{AiChatMessage, AiConfig, AiConversation};
 use crate::db::sqlite::{connect_path_create_if_missing, SqliteHandle};
@@ -355,6 +356,48 @@ impl Storage {
         };
         Ok(array.iter().filter_map(|item| item.as_str().map(|value| value.to_string())).collect())
     }
+
+    pub async fn load_or_create_local_device_secret(&self) -> Result<String, String> {
+        let mut settings = self.load_app_settings_json().await?;
+        if let Some(secret) = settings.get("local_device_secret").and_then(|value| value.as_str()) {
+            if !secret.is_empty() {
+                return Ok(secret.to_string());
+            }
+        }
+        let secret = Uuid::new_v4().to_string();
+        settings.insert("local_device_secret".to_string(), serde_json::Value::String(secret.clone()));
+        self.save_app_settings_json(&settings).await?;
+        Ok(secret)
+    }
+
+    pub async fn save_webdav_password_blob(&self, account: &str, blob: &serde_json::Value) -> Result<(), String> {
+        let mut settings = self.load_app_settings_json().await?;
+        let mut credentials =
+            settings.remove("webdav_passwords").and_then(|value| value.as_object().cloned()).unwrap_or_default();
+        credentials.insert(account.to_string(), blob.clone());
+        settings.insert("webdav_passwords".to_string(), serde_json::Value::Object(credentials));
+        self.save_app_settings_json(&settings).await
+    }
+
+    pub async fn load_webdav_password_blob(&self, account: &str) -> Result<Option<serde_json::Value>, String> {
+        let settings = self.load_app_settings_json().await?;
+        Ok(settings
+            .get("webdav_passwords")
+            .and_then(|value| value.as_object())
+            .and_then(|credentials| credentials.get(account))
+            .cloned())
+    }
+
+    pub async fn delete_webdav_password_blob(&self, account: &str) -> Result<(), String> {
+        let mut settings = self.load_app_settings_json().await?;
+        let Some(mut credentials) = settings.remove("webdav_passwords").and_then(|value| value.as_object().cloned())
+        else {
+            return Ok(());
+        };
+        credentials.remove(account);
+        settings.insert("webdav_passwords".to_string(), serde_json::Value::Object(credentials));
+        self.save_app_settings_json(&settings).await
+    }
 }
 
 // AI Conversations
@@ -432,6 +475,45 @@ impl Storage {
 // Connections
 
 impl Storage {
+    pub async fn save_connection_metadata_preserving_secrets(
+        &self,
+        configs: &[ConnectionConfig],
+    ) -> Result<(), String> {
+        let configs = configs.to_vec();
+        self.with_conn(move |conn| {
+            let tx = conn.transaction().map_err(|e| e.to_string())?;
+            tx.execute("DELETE FROM connections", []).map_err(|e| e.to_string())?;
+
+            for config in &configs {
+                let config = config.canonicalized();
+                let config_id = config.id.clone();
+                let mut sanitized = config;
+                sanitized.password = String::new();
+                sanitized.ssh_password = String::new();
+                sanitized.ssh_key_passphrase = String::new();
+                sanitized.proxy_password = String::new();
+                sanitized.redis_sentinel_password = String::new();
+                sanitized.connection_string = None;
+                let json = serde_json::to_string(&sanitized).map_err(|e| e.to_string())?;
+
+                tx.execute("INSERT INTO connections (id, config_json) VALUES (?1, ?2)", params![config_id, json])
+                    .map_err(|e| e.to_string())?;
+            }
+
+            if configs.is_empty() {
+                tx.execute("DELETE FROM connection_secrets", []).map_err(|e| e.to_string())?;
+            } else {
+                let placeholders = vec!["?"; configs.len()].join(",");
+                let sql = format!("DELETE FROM connection_secrets WHERE connection_id NOT IN ({placeholders})");
+                let ids = configs.iter().map(|config| &config.id as &dyn ToSql);
+                tx.execute(&sql, params_from_iter(ids)).map_err(|e| e.to_string())?;
+            }
+
+            tx.commit().map_err(|e| e.to_string())
+        })
+        .await
+    }
+
     pub async fn save_connections(&self, configs: &[ConnectionConfig]) -> Result<(), String> {
         let configs = configs.to_vec();
         self.with_conn(move |conn| {
@@ -512,6 +594,47 @@ impl Storage {
 // Saved SQL
 
 impl Storage {
+    pub async fn replace_saved_sql_library(&self, library: &SavedSqlLibrary) -> Result<(), String> {
+        let library = library.clone();
+        self.with_conn(move |conn| {
+            let tx = conn.transaction().map_err(|e| e.to_string())?;
+            tx.execute("DELETE FROM saved_sql_files", []).map_err(|e| e.to_string())?;
+            tx.execute("DELETE FROM saved_sql_folders", []).map_err(|e| e.to_string())?;
+
+            for folder in &library.folders {
+                tx.execute(
+                    "INSERT INTO saved_sql_folders (id, connection_id, name, created_at, updated_at) \
+                     VALUES (?, ?, ?, ?, ?)",
+                    params![folder.id, folder.connection_id, folder.name, folder.created_at, folder.updated_at],
+                )
+                .map_err(|e| e.to_string())?;
+            }
+
+            for file in &library.files {
+                tx.execute(
+                    "INSERT INTO saved_sql_files \
+                     (id, connection_id, folder_id, name, database_name, schema_name, sql_text, created_at, updated_at) \
+                     VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)",
+                    params![
+                        file.id,
+                        file.connection_id,
+                        file.folder_id,
+                        file.name,
+                        file.database,
+                        file.schema,
+                        file.sql,
+                        file.created_at,
+                        file.updated_at
+                    ],
+                )
+                .map_err(|e| e.to_string())?;
+            }
+
+            tx.commit().map_err(|e| e.to_string())
+        })
+        .await
+    }
+
     pub async fn load_saved_sql_library(&self) -> Result<SavedSqlLibrary, String> {
         self.with_conn(|conn| {
             let mut folder_stmt = conn
diff --git a/src-tauri/src/commands/cloud_sync.rs b/src-tauri/src/commands/cloud_sync.rs
new file mode 100644
index 000000000..2eeca1428
--- /dev/null
+++ b/src-tauri/src/commands/cloud_sync.rs
@@ -0,0 +1,85 @@
+use std::sync::Arc;
+
+use dbx_core::cloud_sync::{
+    apply_sync_snapshot, build_sync_snapshot, forget_webdav_password, resolve_webdav_password, save_webdav_password,
+    webdav_saved_password_status, ApplySnapshotOptions, ApplySnapshotSummary, WebDavClient, WebDavConfig,
+    WebDavPasswordStatus, WebDavSyncSummary,
+};
+use dbx_core::storage::DesktopSettings;
+use serde::{Deserialize, Serialize};
+use tauri::State;
+
+use dbx_core::connection::AppState;
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct WebDavDownloadResult {
+    pub summary: WebDavSyncSummary,
+    pub editor_settings: Option<serde_json::Value>,
+    pub desktop_settings: DesktopSettings,
+    pub apply_summary: ApplySnapshotSummary,
+}
+
+#[tauri::command]
+pub async fn webdav_sync_test(state: State<'_, Arc<AppState>>, mut config: WebDavConfig) -> Result<(), String> {
+    resolve_webdav_password(&state.storage, &mut config).await?;
+    WebDavClient::new(config).test().await
+}
+
+#[tauri::command]
+pub async fn webdav_password_status(
+    state: State<'_, Arc<AppState>>,
+    config: WebDavConfig,
+) -> Result<WebDavPasswordStatus, String> {
+    webdav_saved_password_status(&state.storage, &config).await
+}
+
+#[tauri::command]
+pub async fn save_webdav_saved_password(
+    state: State<'_, Arc<AppState>>,
+    config: WebDavConfig,
+    password: String,
+) -> Result<(), String> {
+    save_webdav_password(&state.storage, &config, &password).await
+}
+
+#[tauri::command]
+pub async fn forget_webdav_saved_password(state: State<'_, Arc<AppState>>, config: WebDavConfig) -> Result<(), String> {
+    forget_webdav_password(&state.storage, &config).await
+}
+
+#[tauri::command]
+pub async fn webdav_sync_upload(
+    state: State<'_, Arc<AppState>>,
+    mut config: WebDavConfig,
+    editor_settings: Option<serde_json::Value>,
+    secrets_passphrase: Option<String>,
+) -> Result<WebDavSyncSummary, String> {
+    resolve_webdav_password(&state.storage, &mut config).await?;
+    let snapshot =
+        build_sync_snapshot(&state.storage, env!("CARGO_PKG_VERSION"), editor_settings, secrets_passphrase.as_deref())
+            .await?;
+    WebDavClient::new(config).put_snapshot(&snapshot).await
+}
+
+#[tauri::command]
+pub async fn webdav_sync_download(
+    state: State<'_, Arc<AppState>>,
+    mut config: WebDavConfig,
+    secrets_passphrase: Option<String>,
+) -> Result<WebDavDownloadResult, String> {
+    resolve_webdav_password(&state.storage, &mut config).await?;
+    let (snapshot, summary) = WebDavClient::new(config).get_snapshot().await?;
+    let apply_summary = apply_sync_snapshot(
+        &state.storage,
+        &snapshot,
+        ApplySnapshotOptions { secrets_passphrase: secrets_passphrase.as_deref() },
+    )
+    .await?;
+    Ok(WebDavDownloadResult {
+        summary,
+        editor_settings: snapshot.editor_settings,
+        desktop_settings: snapshot.desktop_settings,
+        apply_summary,
+    })
+}
diff --git a/src-tauri/src/commands/mod.rs b/src-tauri/src/commands/mod.rs
index 86a364718..e221271ac 100644
--- a/src-tauri/src/commands/mod.rs
+++ b/src-tauri/src/commands/mod.rs
@@ -1,6 +1,7 @@
 pub mod agents;
 pub mod ai;
 pub mod app_settings;
+pub mod cloud_sync;
 pub mod connection;
 #[allow(dead_code, unused_imports)]
 mod connection_secrets;
diff --git a/src-tauri/src/lib.rs b/src-tauri/src/lib.rs
index da83f73f2..1932972e1 100644
--- a/src-tauri/src/lib.rs
+++ b/src-tauri/src/lib.rs
@@ -247,6 +247,12 @@ pub fn run() {
             commands::app_settings::save_desktop_settings,
             commands::app_settings::load_pinned_tree_node_ids,
             commands::app_settings::save_pinned_tree_node_ids,
+            commands::cloud_sync::webdav_sync_test,
+            commands::cloud_sync::webdav_password_status,
+            commands::cloud_sync::save_webdav_saved_password,
+            commands::cloud_sync::forget_webdav_saved_password,
+            commands::cloud_sync::webdav_sync_upload,
+            commands::cloud_sync::webdav_sync_download,
             commands::connection::test_connection,
             commands::connection::connect_db,
             commands::connection::disconnect_db,