diff --git a/components/Avatar/Avatar.php b/components/Avatar/Avatar.php
index f378d1d6f8..cc60aa59f6 100644
--- a/components/Avatar/Avatar.php
+++ b/components/Avatar/Avatar.php
@@ -29,6 +29,8 @@ use App\Core\Modules\Component;
 use App\Core\Router\RouteLoader;
 use App\Core\Router\Router;
 use App\Util\Common;
+use Component\Attachment\Entity\Attachment;
+use Component\Attachment\Entity\AttachmentThumbnail;
 use Component\Avatar\Controller as C;
 use Component\Avatar\Exception\NoAvatarException;
 use Symfony\Component\HttpFoundation\Request;
@@ -41,8 +43,8 @@ class Avatar extends Component
 
     public function onAddRoute(RouteLoader $r): bool
     {
-        $r->connect('avatar_actor', '/actor/{actor_id<\d+>}/avatar/{size<full|big|medium|small>?full}', [Controller\Avatar::class, 'avatar_view']);
-        $r->connect('avatar_default', '/avatar/default/{size<full|big|medium|small>?full}', [Controller\Avatar::class, 'default_avatar_view']);
+        $r->connect('avatar_actor', '/actor/{actor_id<\d+>}/avatar/{size<full|big|medium|small>?medium}', [Controller\Avatar::class, 'avatar_view']);
+        $r->connect('avatar_default', '/avatar/default/{size<full|big|medium|small>?medium}', [Controller\Avatar::class, 'default_avatar_view']);
         $r->connect('avatar_settings', '/settings/avatar', [Controller\Avatar::class, 'settings_avatar']);
         return Event::next;
     }
@@ -102,7 +104,7 @@ class Avatar extends Component
     /**
      * Get the cached avatar associated with the given Actor id, or the current user if not given
      */
-    public static function getUrl(int $actor_id, string $size = 'full', int $type = Router::ABSOLUTE_PATH): string
+    public static function getUrl(int $actor_id, string $size = 'medium', int $type = Router::ABSOLUTE_PATH): string
     {
         try {
             return self::getAvatar($actor_id)->getUrl($size, $type);
@@ -111,11 +113,12 @@ class Avatar extends Component
         }
     }
 
-    public static function getDimensions(int $actor_id, string $size = 'full')
+    public static function getDimensions(int $actor_id, string $size = 'medium')
     {
         try {
-            $attachment = self::getAvatar($actor_id)->getAttachment();
-            return ['width' => $attachment->getWidth(), 'height' => $attachment->getHeight()];
+            $avatar = self::getAvatar($actor_id);
+            $a      = $size === 'full' ? $avatar->getAttachment() : $avatar->getAttachmentThumbnail($size);
+            return ['width' => $a->getWidth(), 'height' => $a->getHeight()];
         } catch (NoAvatarException) {
             return ['width' => Common::config('thumbnail', 'small'), 'height' => Common::config('thumbnail', 'small')];
         }
@@ -127,7 +130,7 @@ class Avatar extends Component
      * Returns the avatar file's hash, mimetype, title and path.
      * Ensures exactly one cached value exists
      */
-    public static function getAvatarFileInfo(int $actor_id, string $size = 'full'): array
+    public static function getAvatarFileInfo(int $actor_id, string $size = 'medium'): array
     {
         $res = Cache::get(
             "avatar-file-info-{$actor_id}-{$size}",
@@ -151,8 +154,12 @@ class Avatar extends Component
                 'title'    => 'default_avatar.svg',
             ];
         } else {
-            $res             = $res[0]; // A user must always only have one avatar.
-            $res['filepath'] = DB::findOneBy('attachment', ['id' => $res['id']])->getPath();
+            $res = $res[0]; // A user must always only have one avatar.
+            if ($size === 'full') {
+                $res['filepath'] = Attachment::getByPK(['id' => $res['id']])->getPath();
+            } else {
+                $res['filepath'] = AttachmentThumbnail::getOrCreate(Attachment::getByPK(['id' => $res['id']]), $size)->getPath();
+            }
             return $res;
         }
     }
diff --git a/components/Avatar/Controller/Avatar.php b/components/Avatar/Controller/Avatar.php
index dbd4573b65..d51d2b5449 100644
--- a/components/Avatar/Controller/Avatar.php
+++ b/components/Avatar/Controller/Avatar.php
@@ -57,13 +57,8 @@ class Avatar extends Controller
      */
     public function avatar_view(Request $request, int $actor_id, string $size): Response
     {
-        switch ($size) {
-            case 'full':
-                $res = \Component\Avatar\Avatar::getAvatarFileInfo($actor_id);
-                return M::sendFile($res['filepath'], $res['mimetype'], $res['title']);
-            default:
-                throw new Exception('Not implemented');
-        }
+        $res = \Component\Avatar\Avatar::getAvatarFileInfo($actor_id, $size);
+        return M::sendFile($res['filepath'], $res['mimetype'], $res['title']);
     }
 
     /**
diff --git a/components/Avatar/Entity/Avatar.php b/components/Avatar/Entity/Avatar.php
index 3b9bd4bbf2..88f8b0dd05 100644
--- a/components/Avatar/Entity/Avatar.php
+++ b/components/Avatar/Entity/Avatar.php
@@ -29,6 +29,7 @@ use App\Core\Entity;
 use App\Core\Router\Router;
 use App\Util\Common;
 use Component\Attachment\Entity\Attachment;
+use Component\Attachment\Entity\AttachmentThumbnail;
 use DateTimeInterface;
 
 /**
@@ -115,7 +116,7 @@ class Avatar extends Entity
 
     private ?Attachment $attachment = null;
 
-    public function getUrl(string $size = 'full', int $type = Router::ABSOLUTE_PATH): string
+    public function getUrl(string $size = 'medium', int $type = Router::ABSOLUTE_PATH): string
     {
         $actor_id = $this->getActorId();
         return Cache::get("avatar-url-{$actor_id}-{$size}-{$type}", fn () => Router::url('avatar_actor', ['actor_id' => $actor_id, 'size' => $size], $type));
@@ -123,10 +124,15 @@ class Avatar extends Entity
 
     public function getAttachment(): Attachment
     {
-        $this->attachment ??= DB::findOneBy('attachment', ['id' => $this->attachment_id]);
+        $this->attachment ??= DB::findOneBy('attachment', ['id' => $this->getAttachmentId()]);
         return $this->attachment;
     }
 
+    public function getAttachmentThumbnail(string $size): ?AttachmentThumbnail
+    {
+        return AttachmentThumbnail::getOrCreate($this->getAttachment(), $size);
+    }
+
     public static function getFilePathStatic(string $filename): string
     {
         return Common::config('avatar', 'dir') . $filename;
diff --git a/src/Entity/Actor.php b/src/Entity/Actor.php
index 180bccd195..d6368cd1e1 100644
--- a/src/Entity/Actor.php
+++ b/src/Entity/Actor.php
@@ -288,12 +288,12 @@ class Actor extends Entity
         }
     }
 
-    public function getAvatarUrl(string $size = 'full')
+    public function getAvatarUrl(string $size = 'medium')
     {
         return Avatar::getUrl($this->getId(), $size);
     }
 
-    public function getAvatarDimensions(string $size = 'full')
+    public function getAvatarDimensions(string $size = 'medium')
     {
         return Avatar::getDimensions($this->getId(), $size);
     }
diff --git a/src/Entity/Note.php b/src/Entity/Note.php
index f96ee7d004..5ca45bfb3e 100644
--- a/src/Entity/Note.php
+++ b/src/Entity/Note.php
@@ -252,7 +252,7 @@ class Note extends Entity
         return Actor::getFullnameById($this->actor_id);
     }
 
-    public function getActorAvatarUrl(string $size = 'full'): string
+    public function getActorAvatarUrl(string $size = 'medium'): string
     {
         return Avatar::getUrl($this->getActorId(), $size);
     }