diff --git a/src/App.tsx b/src/App.tsx
index d48df9b..5b1e4c5 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -5,6 +5,7 @@ import { Library } from "./components/Library";
 import { EditorView } from "./components/EditorView";
 import { BackupSettings } from "./components/BackupSettings";
 import { ExportPreview } from "./components/ExportPreview";
+import { UpdateDialog } from "./components/UpdateDialog";
 import { useBook } from "./store/useBook";
 import { useBackup } from "./store/useBackup";
 import { useExportPreview } from "./store/useExportPreview";
@@ -87,6 +88,7 @@ function App() {
       {book ? <EditorView /> : <Library onOpen={openBook} />}
       {isDesktop && <BackupSettings />}
       {isDesktop && <ExportPreview />}
+      {isDesktop && <UpdateDialog />}
     </>
   );
 }
diff --git a/src/components/UpdateDialog.tsx b/src/components/UpdateDialog.tsx
new file mode 100644
index 0000000..ea34996
--- /dev/null
+++ b/src/components/UpdateDialog.tsx
@@ -0,0 +1,104 @@
+import { useUpdater } from "../store/useUpdater";
+import { installUpdate, dismissUpdate } from "../updater";
+import { Icon } from "./Icon";
+
+const TITLES: Record<string, string> = {
+  checking: "Check for Updates",
+  available: "Update Available",
+  downloading: "Updating margin",
+  installing: "Updating margin",
+  uptodate: "Check for Updates",
+  error: "Update Failed",
+};
+
+export function UpdateDialog() {
+  const phase = useUpdater((s) => s.phase);
+  const version = useUpdater((s) => s.version);
+  const notes = useUpdater((s) => s.notes);
+  const downloaded = useUpdater((s) => s.downloaded);
+  const total = useUpdater((s) => s.total);
+  const error = useUpdater((s) => s.error);
+
+  if (phase === "idle") return null;
+
+  const busy = phase === "downloading" || phase === "installing";
+  const pct = total > 0 ? Math.min(100, Math.round((downloaded / total) * 100)) : 0;
+  const close = busy ? undefined : dismissUpdate;
+
+  return (
+    <div className="overlay" onClick={close}>
+      <div className="panel panel-confirm" onClick={(e) => e.stopPropagation()}>
+        <div className="panel-head">
+          <h2>{TITLES[phase]}</h2>
+          {!busy && (
+            <button className="icon-btn" onClick={dismissUpdate} title="Close">
+              <Icon d="M6 6l12 12M18 6L6 18" />
+            </button>
+          )}
+        </div>
+
+        <div className="panel-body">
+          {phase === "checking" && (
+            <div className="update-status-row">
+              <span className="update-spinner" />
+              <span>Checking for updates…</span>
+            </div>
+          )}
+
+          {phase === "uptodate" && <p className="confirm-text">margin is up to date.</p>}
+
+          {phase === "available" && (
+            <>
+              <p className="confirm-text">
+                <strong>margin {version}</strong> is available.
+              </p>
+              {notes && <div className="update-notes">{notes}</div>}
+            </>
+          )}
+
+          {phase === "downloading" && (
+            <>
+              <div className={`update-progress${total > 0 ? "" : " indeterminate"}`}>
+                <div className="update-progress-fill" style={total > 0 ? { width: `${pct}%` } : undefined} />
+              </div>
+              <p className="update-status">{total > 0 ? `Downloading update… ${pct}%` : "Downloading update…"}</p>
+            </>
+          )}
+
+          {phase === "installing" && (
+            <div className="update-status-row">
+              <span className="update-spinner" />
+              <span>Installing update. margin will restart…</span>
+            </div>
+          )}
+
+          {phase === "error" && (
+            <>
+              <p className="confirm-text">Could not update margin.</p>
+              {error && <div className="update-notes">{error}</div>}
+            </>
+          )}
+        </div>
+
+        {phase === "available" && (
+          <div className="panel-foot">
+            <button className="btn-ghost" onClick={dismissUpdate}>
+              Later
+            </button>
+            <button className="btn-primary" onClick={installUpdate}>
+              Install &amp; Restart
+            </button>
+          </div>
+        )}
+
+        {(phase === "uptodate" || phase === "error") && (
+          <div className="panel-foot">
+            <button className="btn-primary" onClick={dismissUpdate}>
+              OK
+            </button>
+          </div>
+        )}
+      </div>
+    </div>
+  );
+}
diff --git a/src/store/useUpdater.ts b/src/store/useUpdater.ts
new file mode 100644
index 0000000..bc18fbb
--- /dev/null
+++ b/src/store/useUpdater.ts
@@ -0,0 +1,39 @@
+import { create } from "zustand";
+import type { Update } from "@tauri-apps/plugin-updater";
+
+export type UpdatePhase =
+  | "idle"
+  | "checking"
+  | "available"
+  | "downloading"
+  | "installing"
+  | "uptodate"
+  | "error";
+
+interface UpdaterState {
+  phase: UpdatePhase;
+  version: string;
+  notes: string;
+  downloaded: number;
+  total: number;
+  error: string;
+  update: Update | null;
+  set: (partial: Partial<UpdaterState>) => void;
+  reset: () => void;
+}
+
+const initial = {
+  phase: "idle" as UpdatePhase,
+  version: "",
+  notes: "",
+  downloaded: 0,
+  total: 0,
+  error: "",
+  update: null as Update | null,
+};
+
+export const useUpdater = create<UpdaterState>((set) => ({
+  ...initial,
+  set: (partial) => set(partial),
+  reset: () => set(initial),
+}));
diff --git a/src/styles/app.css b/src/styles/app.css
index fbf8493..cea5e82 100644
--- a/src/styles/app.css
+++ b/src/styles/app.css
@@ -1615,6 +1615,72 @@ body.resizing .sidebar {
   color: var(--ink);
 }
 
+.update-notes {
+  max-height: 180px;
+  overflow-y: auto;
+  padding: 12px 14px;
+  border: 1px solid var(--line);
+  border-radius: var(--r-sm);
+  background: var(--raised);
+  font-size: var(--t-3);
+  line-height: 1.55;
+  color: var(--ink-soft);
+  white-space: pre-line;
+}
+
+.update-status-row {
+  display: flex;
+  align-items: center;
+  gap: 11px;
+  font-size: var(--t-4);
+  color: var(--ink-soft);
+}
+
+.update-spinner {
+  flex: none;
+  width: 18px;
+  height: 18px;
+  border: 2px solid var(--line-strong);
+  border-top-color: var(--accent);
+  border-radius: 50%;
+  animation: spin 0.7s linear infinite;
+}
+
+.update-progress {
+  width: 100%;
+  height: 7px;
+  border-radius: 999px;
+  background: var(--accent-wash);
+  overflow: hidden;
+}
+
+.update-progress-fill {
+  height: 100%;
+  border-radius: 999px;
+  background: var(--accent);
+  transition: width 160ms var(--ease);
+}
+
+.update-progress.indeterminate .update-progress-fill {
+  width: 40%;
+  animation: update-indeterminate 1.1s ease-in-out infinite;
+}
+
+@keyframes update-indeterminate {
+  0% {
+    transform: translateX(-120%);
+  }
+  100% {
+    transform: translateX(320%);
+  }
+}
+
+.update-status {
+  margin: 0;
+  font-size: var(--t-3);
+  color: var(--ink-soft);
+}
+
 .btn-primary,
 .btn-ghost,
 .btn-danger {
diff --git a/src/updater.ts b/src/updater.ts
index 8af20d6..4784587 100644
--- a/src/updater.ts
+++ b/src/updater.ts
@@ -1,31 +1,58 @@
 import { check } from "@tauri-apps/plugin-updater";
 import { relaunch } from "@tauri-apps/plugin-process";
-import { ask, message } from "@tauri-apps/plugin-dialog";
+import { useUpdater } from "./store/useUpdater";
 
-let running = false;
+let checking = false;
 
 export async function checkForUpdates(silent: boolean) {
-  if (running) return;
-  running = true;
+  if (checking) return;
+  checking = true;
+  const store = useUpdater.getState();
+  if (!silent) store.set({ phase: "checking", error: "" });
   try {
     const update = await check();
     if (!update) {
-      if (!silent) await message("margin is up to date.", { title: "Check for Updates" });
+      store.set(silent ? { phase: "idle" } : { phase: "uptodate" });
       return;
     }
-    const notes = update.body ? `\n\n${update.body}` : "";
-    const install = await ask(`margin ${update.version} is available.${notes}\n\nInstall now and restart?`, {
-      title: "Update Available",
-      kind: "info",
+    store.set({
+      phase: "available",
+      update,
+      version: update.version,
+      notes: update.body ?? "",
+      downloaded: 0,
+      total: 0,
+      error: "",
     });
-    if (!install) return;
-    await update.downloadAndInstall();
-    await relaunch();
   } catch (err) {
-    if (!silent) {
-      await message(`Could not check for updates.\n\n${err}`, { title: "Update Failed", kind: "error" });
-    }
+    store.set(silent ? { phase: "idle" } : { phase: "error", error: String(err) });
   } finally {
-    running = false;
+    checking = false;
   }
 }
+
+export async function installUpdate() {
+  const { update, phase } = useUpdater.getState();
+  if (!update || phase === "downloading" || phase === "installing") return;
+  try {
+    useUpdater.getState().set({ phase: "downloading", downloaded: 0, total: 0 });
+    await update.downloadAndInstall((event) => {
+      const s = useUpdater.getState();
+      if (event.event === "Started") {
+        s.set({ total: event.data.contentLength ?? 0, downloaded: 0 });
+      } else if (event.event === "Progress") {
+        s.set({ downloaded: s.downloaded + event.data.chunkLength });
+      } else if (event.event === "Finished") {
+        s.set({ phase: "installing" });
+      }
+    });
+    useUpdater.getState().set({ phase: "installing" });
+    await relaunch();
+  } catch (err) {
+    useUpdater.getState().set({ phase: "error", error: String(err) });
+  }
+}
+
+export function dismissUpdate() {
+  useUpdater.getState().reset();
+}