diff --git a/src/calibre/gui2/dialogs/comments_dialog.ui b/src/calibre/gui2/dialogs/comments_dialog.ui
index 9c6e6cb861..76b23e233d 100644
--- a/src/calibre/gui2/dialogs/comments_dialog.ui
+++ b/src/calibre/gui2/dialogs/comments_dialog.ui
@@ -6,8 +6,8 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>336</width>
-    <height>235</height>
+    <width>400</width>
+    <height>400</height>
    </rect>
   </property>
   <property name="sizePolicy">