diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index bd060c3a1f..72c1d35e5f 100644
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -8405,6 +8405,8 @@ gtk_window_get_preferred_width_for_height (GtkWidget *widget,
     {
       get_shadow_width (widget, &window_border);
 
+      height -= window_border.top + window_border.bottom;
+
       if (priv->title_box != NULL &&
           gtk_widget_get_visible (priv->title_box) &&
           gtk_widget_get_child_visible (priv->title_box))
@@ -8515,6 +8517,8 @@ gtk_window_get_preferred_height_for_width (GtkWidget *widget,
     {
       get_shadow_width (widget, &window_border);
 
+      width -= window_border.left + window_border.right;
+
       if (priv->title_box != NULL &&
           gtk_widget_get_visible (priv->title_box) &&
           gtk_widget_get_child_visible (priv->title_box))