diff --git a/cutleft.py b/cutleft.py
index 83f7f43..1eb7393 100644
--- a/cutleft.py
+++ b/cutleft.py
@@ -307,8 +307,9 @@ class ImageReviewer:
         preview, splits, schema = result
         self.current_preview = preview
 
-        # Save immediately upon loading/calculating
-        save_results(result, filename)
+        # Save in a background thread so the GUI updates instantly
+        Thread(target=save_results, args=(result, filename), daemon=True).start()
+
         self.update_display(filename, schema)
 
     def update_display(self, filename, schema=None):