diff --git a/backend/actions/status.js b/backend/actions/status.js
index 43f1e5b2..820fdd5e 100644
--- a/backend/actions/status.js
+++ b/backend/actions/status.js
@@ -1,7 +1,22 @@
 'use strict';
 
 const nodeEnv = process.env.NODE_ENV;
+const DEFAULT_INACTIVITY_TIMEOUT_MINUTES = 15;
+
+function parseInactivityTimeoutMinutes() {
+  const raw = process.env.INACTIVITY_TIMEOUT_MINUTES;
+  if (raw == null || raw === '') {
+    return DEFAULT_INACTIVITY_TIMEOUT_MINUTES;
+  }
+  const parsed = Number(raw);
+  if (!Number.isFinite(parsed) || parsed <= 0) {
+    return DEFAULT_INACTIVITY_TIMEOUT_MINUTES;
+  }
+  return parsed;
+}
+
+const inactivityTimeoutMinutes = parseInactivityTimeoutMinutes();
 
 module.exports = () => async function status() {
-  return { nodeEnv };
+  return { nodeEnv, inactivityTimeoutMinutes };
 };
diff --git a/frontend/src/_util/inactivity-timeout.js b/frontend/src/_util/inactivity-timeout.js
new file mode 100644
index 00000000..2a7117ef
--- /dev/null
+++ b/frontend/src/_util/inactivity-timeout.js
@@ -0,0 +1,110 @@
+'use strict';
+
+const DEFAULT_INACTIVITY_TIMEOUT_MS = 15 * 60 * 1000;
+const LAST_ACTIVITY_STORAGE_KEY = 'studio:last-activity-at';
+const ACTIVITY_THROTTLE_MS = 1000;
+const ACTIVITY_EVENTS = ['mousedown', 'mousemove', 'keydown', 'touchstart', 'scroll', 'click'];
+
+function isProductionEnv(nodeEnv) {
+  return nodeEnv === 'prod' || nodeEnv === 'production';
+}
+
+function logout() {
+  window.localStorage.setItem('_mongooseStudioAccessToken', '');
+  window.localStorage.removeItem(LAST_ACTIVITY_STORAGE_KEY);
+  window.location.reload();
+}
+
+let inactivityTimeoutMs = DEFAULT_INACTIVITY_TIMEOUT_MS;
+
+function hasTimedOut(lastActivityAt) {
+  return lastActivityAt > 0 && Date.now() - lastActivityAt >= inactivityTimeoutMs;
+}
+
+let timeoutId = null;
+let started = false;
+let lastResetAt = 0;
+
+function recordActivity() {
+  window.localStorage.setItem(LAST_ACTIVITY_STORAGE_KEY, String(Date.now()));
+}
+
+function resetTimeout() {
+  if (timeoutId) {
+    clearTimeout(timeoutId);
+  }
+  recordActivity();
+  timeoutId = setTimeout(logout, inactivityTimeoutMs);
+}
+
+function onActivity() {
+  const now = Date.now();
+  if (now - lastResetAt < ACTIVITY_THROTTLE_MS) {
+    return;
+  }
+  lastResetAt = now;
+  resetTimeout();
+}
+
+function onVisibilityChange() {
+  if (document.visibilityState !== 'visible') {
+    return;
+  }
+  const lastActivityAt = Number(window.localStorage.getItem(LAST_ACTIVITY_STORAGE_KEY));
+  if (hasTimedOut(lastActivityAt)) {
+    logout();
+  }
+}
+
+function stopInactivityTimeout() {
+  if (timeoutId) {
+    clearTimeout(timeoutId);
+    timeoutId = null;
+  }
+  for (const event of ACTIVITY_EVENTS) {
+    window.removeEventListener(event, onActivity, true);
+  }
+  document.removeEventListener('visibilitychange', onVisibilityChange);
+  started = false;
+  lastResetAt = 0;
+  inactivityTimeoutMs = DEFAULT_INACTIVITY_TIMEOUT_MS;
+}
+
+function resolveInactivityTimeoutMs(timeoutMinutes) {
+  if (timeoutMinutes != null && Number.isFinite(timeoutMinutes) && timeoutMinutes > 0) {
+    return timeoutMinutes * 60 * 1000;
+  }
+  return DEFAULT_INACTIVITY_TIMEOUT_MS;
+}
+
+function startInactivityTimeout(nodeEnv, { freshLogin = false, timeoutMinutes } = {}) {
+  if (!isProductionEnv(nodeEnv)) {
+    return;
+  }
+  if (started) {
+    return;
+  }
+  started = true;
+  inactivityTimeoutMs = resolveInactivityTimeoutMs(timeoutMinutes);
+
+  if (!freshLogin) {
+    const lastActivityAt = Number(window.localStorage.getItem(LAST_ACTIVITY_STORAGE_KEY));
+    if (hasTimedOut(lastActivityAt)) {
+      logout();
+      return;
+    }
+  }
+
+  for (const event of ACTIVITY_EVENTS) {
+    window.addEventListener(event, onActivity, { capture: true, passive: true });
+  }
+  document.addEventListener('visibilitychange', onVisibilityChange);
+
+  resetTimeout();
+}
+
+module.exports = {
+  startInactivityTimeout,
+  stopInactivityTimeout,
+  isProductionEnv
+};
diff --git a/frontend/src/index.js b/frontend/src/index.js
index 64d07f6f..823b4033 100644
--- a/frontend/src/index.js
+++ b/frontend/src/index.js
@@ -22,6 +22,7 @@ const {
   normalizeTrackedPath,
   withRecentPagesStorageLock
 } = require('./_util/recent-pages-history');
+const { startInactivityTimeout } = require('./_util/inactivity-timeout');
 appendCSS(require('vue-toastification/dist/index.css'));
 
 const TRACKED_RECENT_PAGE_ROUTE_NAMES = new Set(['model', 'document', 'dashboard', 'chat']);
@@ -214,6 +215,9 @@ app.component('app-component', {
     window.$router = this.$router;
     window.state = this;
 
+    let freshLogin = false;
+    let inactivityTimeoutMinutes = 15;
+
     if (mothership.hasAPIKey) {
       const hash = window.location.hash.replace(/^#?\/?/, '') || '';
       const hashQuery = hash.split('?')[1] || '';
@@ -241,11 +245,12 @@ app.component('app-component', {
         window.localStorage.setItem('_mongooseStudioAccessToken', accessToken._id);
 
         try {
-          const [{ nodeEnv }, capabilities] = await Promise.all([
+          const [{ nodeEnv, inactivityTimeoutMinutes: timeoutMinutes }, capabilities] = await Promise.all([
             api.status(),
             loadStudioCapabilities()
           ]);
           this.nodeEnv = nodeEnv;
+          inactivityTimeoutMinutes = timeoutMinutes;
           this.capabilities = capabilities;
         } catch (err) {
           this.authError = 'Error connecting to Mongoose Studio API: ' + err.response?.data?.message ?? err.message;
@@ -256,6 +261,7 @@ app.component('app-component', {
 
         this.user = user;
         this.roles = roles;
+        freshLogin = true;
 
         setTimeout(() => {
           this.$router.replace(this.$router.currentRoute.value.path);
@@ -266,12 +272,13 @@ app.component('app-component', {
           const { user, roles } = await mothership.me();
 
           try {
-            const [{ nodeEnv }, { modelSchemaPaths }, capabilities] = await Promise.all([
+            const [{ nodeEnv, inactivityTimeoutMinutes: timeoutMinutes }, { modelSchemaPaths }, capabilities] = await Promise.all([
               api.status(),
               api.Model.listModels(),
               loadStudioCapabilities()
             ]);
             this.nodeEnv = nodeEnv;
+            inactivityTimeoutMinutes = timeoutMinutes;
             this.modelSchemaPaths = modelSchemaPaths;
             this.capabilities = capabilities;
           } catch (err) {
@@ -286,12 +293,13 @@ app.component('app-component', {
       }
     } else {
       try {
-        const [{ nodeEnv }, { modelSchemaPaths }, capabilities] = await Promise.all([
+        const [{ nodeEnv, inactivityTimeoutMinutes: timeoutMinutes }, { modelSchemaPaths }, capabilities] = await Promise.all([
           api.status(),
           api.Model.listModels(),
           loadStudioCapabilities()
         ]);
         this.nodeEnv = nodeEnv;
+        inactivityTimeoutMinutes = timeoutMinutes;
         this.modelSchemaPaths = modelSchemaPaths;
         this.capabilities = capabilities;
       } catch (err) {
@@ -300,6 +308,10 @@ app.component('app-component', {
     }
 
     this.status = 'loaded';
+
+    if (mothership.hasAPIKey && this.user) {
+      startInactivityTimeout(this.nodeEnv, { freshLogin, timeoutMinutes: inactivityTimeoutMinutes });
+    }
   },
   setup() {
     const user = Vue.ref(null);