diff --git a/src/Controller/UserController.php b/src/Controller/UserController.php
index 4b825d0..ea0f86c 100644
--- a/src/Controller/UserController.php
+++ b/src/Controller/UserController.php
@@ -57,6 +57,130 @@ class UserController implements IAuthenticationRequired
         return new HtmlContent('account/account', ['user' => $user->toArray()]);
     }
 
+    public function getGoogleConnectRedirect(): IRedirect
+    {
+        /**
+         * @var User $user
+         */
+        $user = \Container::$request->user();
+
+        $state = bin2hex(random_bytes(16));
+        $nonce = bin2hex(random_bytes(16));
+
+        \Container::$request->session()->set('oauth_state', $state);
+        \Container::$request->session()->set('oauth_nonce', $nonce);
+
+        $oAuth = new GoogleOAuth(new Request());
+
+        $url = $oAuth->getDialogUrl(
+            $state,
+            \Container::$request->getBase() . \Container::$routeCollection->getRoute('account.googleConnect-confirm')->generateLink(),
+            $nonce,
+            $user->getEmail()
+        );
+
+        return new Redirect($url, IRedirect::TEMPORARY);
+    }
+
+    public function getGoogleConnectConfirm(): IContent
+    {
+        $defaultError = 'Authentication with Google failed. Please <a href="' . \Container::$routeCollection->getRoute('account.googleConnect')->generateLink() . '" title="Connect with Google">try again</a>!';
+
+        if (\Container::$request->query('state') !== \Container::$request->session()->get('oauth_state')) {
+            return new HtmlContent('account/google_connect', ['success' => false, 'error' => $defaultError]);
+        }
+
+        $oAuth = new GoogleOAuth(new Request());
+        $tokenData = $oAuth->getToken(
+            \Container::$request->query('code'),
+            \Container::$request->getBase() . \Container::$routeCollection->getRoute('account.googleConnect-confirm')->generateLink()
+        );
+        if (!isset($tokenData['id_token'])) {
+            return new HtmlContent('account/google_connect', ['success' => false, 'error' => $defaultError]);
+        }
+
+        $jwtParser = new JwtParser($tokenData['id_token']);
+        $idToken = $jwtParser->getPayload();
+        if ($idToken['nonce'] !== \Container::$request->session()->get('oauth_nonce')) {
+            return new HtmlContent('account/google_connect', ['success' => false, 'error' => $defaultError]);
+        }
+
+        $anotherUser = $this->userRepository->getByGoogleSub($idToken['sub']);
+        if ($anotherUser !== null) {
+            return new HtmlContent('account/google_connect', [
+                'success' => false,
+                'error' => 'This Google account is linked to another account.'
+            ]);
+        }
+
+        \Container::$request->session()->set('google_user_data', $idToken);
+
+        /**
+         * @var User $user
+         */
+        $user = \Container::$request->user();
+
+        return new HtmlContent('account/google_connect', [
+            'success' => true,
+            'googleAccount' => $idToken['email'],
+            'userEmail' => $user->getEmail()
+        ]);
+    }
+
+    public function connectGoogle(): IContent
+    {
+        /**
+         * @var User $user
+         */
+        $user = \Container::$request->user();
+        if (!$user->checkPassword(\Container::$request->post('password'))) {
+            return new JsonContent([
+                'error' => [
+                    'errorText' => 'The given password is wrong.'
+                ]
+            ]);
+        }
+
+        $googleUserData = \Container::$request->session()->get('google_user_data');
+        $user->setGoogleSub($googleUserData['sub']);
+        \Container::$persistentDataManager->saveToDb($user);
+
+        return new JsonContent(['success' => true]);
+    }
+
+    public function getGoogleDisconnectConfirm(): IContent
+    {
+        /**
+         * @var User $user
+         */
+        $user = \Container::$request->user();
+
+        return new HtmlContent('account/google_disconnect', [
+            'success' => true,
+            'userEmail' => $user->getEmail()
+        ]);
+    }
+
+    public function disconnectGoogle(): IContent
+    {
+        /**
+         * @var User $user
+         */
+        $user = \Container::$request->user();
+        if (!$user->checkPassword(\Container::$request->post('password'))) {
+            return new JsonContent([
+                'error' => [
+                    'errorText' => 'The given password is wrong.'
+                ]
+            ]);
+        }
+
+        $user->setGoogleSub(null);
+        \Container::$persistentDataManager->saveToDb($user);
+
+        return new JsonContent(['success' => true]);
+    }
+
     public function getGoogleAuthenticateRedirect(): IRedirect
     {
         /**
diff --git a/views/account/account.php b/views/account/account.php
index e21ae64..b8bc188 100644
--- a/views/account/account.php
+++ b/views/account/account.php
@@ -33,6 +33,13 @@
             </div>
             <hr>
             <div class="center">
+                <?php if ($user['google_sub'] === null): ?>
+                    <a class="button yellow" href="<?= Container::$routeCollection->getRoute('account.googleConnect')->generateLink() ?>" title="Connect with Google">Connect with Google</a>
+                <?php else: ?>
+                    <?php if ($user['password'] !== null): ?>
+                        <a class="button yellow" href="<?= Container::$routeCollection->getRoute('account.googleDisconnect')->generateLink() ?>" title="Disconnect from Google">Disconnect from Google</a>
+                    <?php endif; ?>
+                <?php endif; ?>
                 <a class="button red" href="/account/delete" title="Delete account">Delete account</a>
             </div>
         </form>
diff --git a/views/account/google_connect.php b/views/account/google_connect.php
new file mode 100644
index 0000000..1779e20
--- /dev/null
+++ b/views/account/google_connect.php
@@ -0,0 +1,22 @@
+@extends(templates/layout_normal)
+
+@section(main)
+    <h2>Connect with Google</h2>
+    <div class="box compactBox">
+        <?php if (!$success): ?>
+            <p class="error justify"><?= $error ?></p>
+        <?php else: ?>
+            <form id="connectGoogleForm" action="<?= Container::$routeCollection->getRoute('account.googleConnect-action')->generateLink() ?>" method="post" data-redirect-on-success="<?= Container::$routeCollection->getRoute('account')->generateLink() ?>">
+                <p class="justify marginBottom">Your account will be connected with the following Google account: <b><?= $googleAccount ?></b></p>
+                <input type="email" style="display: none;" name="email" autocomplete="username" value="<?= $userEmail ?>">
+                <p class="formLabel marginTop">Password</p>
+                <input type="password" class="text big fullWidth" name="password" autocomplete="current-password" required minlength="6" autofocus>
+                <p class="formError justify marginTop"></p>
+                <div class="right marginTop">
+                    <button class="marginRight" type="submit" name="submit"><i class="fa-solid fa-link"></i> Connect</button><!--
+                 --><a class="button gray" href="<?= Container::$routeCollection->getRoute('account')->generateLink() ?>" title="Back to account">Cancel</a>
+                </div>
+            </form>
+        <?php endif; ?>
+    </div>
+@endsection
diff --git a/views/account/google_disconnect.php b/views/account/google_disconnect.php
new file mode 100644
index 0000000..8e383e9
--- /dev/null
+++ b/views/account/google_disconnect.php
@@ -0,0 +1,18 @@
+@extends(templates/layout_normal)
+
+@section(main)
+    <h2>Disconnect from Google</h2>
+    <div class="box compactBox">
+        <form id="connectGoogleForm" action="<?= Container::$routeCollection->getRoute('account.googleDisconnect-action')->generateLink() ?>" method="post" data-redirect-on-success="<?= Container::$routeCollection->getRoute('account')->generateLink() ?>">
+            <p class="justify marginBottom">Your account will be disconnected from the currently set Google account.</p>
+            <input type="email" style="display: none;" name="email" autocomplete="username" value="<?= $userEmail ?>">
+            <p class="formLabel marginTop">Password</p>
+            <input type="password" class="text big fullWidth" name="password" autocomplete="current-password" required minlength="6" autofocus>
+            <p class="formError justify marginTop"></p>
+            <div class="right marginTop">
+                <button class="red marginRight" type="submit" name="submit"><i class="fa-solid fa-link-slash"></i> Disconnect</button><!--
+             --><a class="button gray" href="<?= Container::$routeCollection->getRoute('account')->generateLink() ?>" title="Back to account">Cancel</a>
+            </div>
+        </form>
+    </div>
+@endsection
diff --git a/web.php b/web.php
index c557cfc..33a1b10 100644
--- a/web.php
+++ b/web.php
@@ -57,6 +57,11 @@ Container::$routeCollection->group('account', function (RouteCollection $routeCo
     $routeCollection->post('account-action', '', [UserController::class, 'saveAccount']);
     $routeCollection->get('account.delete', 'delete', [UserController::class, 'getDeleteAccount']);
     $routeCollection->post('account.delete-action', 'delete', [UserController::class, 'deleteAccount']);
+    $routeCollection->get('account.googleConnect', 'googleConnect', [UserController::class, 'getGoogleConnectRedirect']);
+    $routeCollection->get('account.googleConnect-confirm', 'googleConnect/code', [UserController::class, 'getGoogleConnectConfirm']);
+    $routeCollection->post('account.googleConnect-action', 'googleConnect', [UserController::class, 'connectGoogle']);
+    $routeCollection->get('account.googleDisconnect', 'googleDisconnect', [UserController::class, 'getGoogleDisconnectConfirm']);
+    $routeCollection->post('account.googleDisconnect-action', 'googleDisconnect', [UserController::class, 'disconnectGoogle']);
     $routeCollection->get('account.googleAuthenticate', 'googleAuthenticate', [UserController::class, 'getGoogleAuthenticateRedirect']);
     $routeCollection->get('account.googleAuthenticate-action', 'googleAuthenticate/code', [UserController::class, 'authenticateWithGoogle']);
 });