diff --git a/util/uncompressedsize.py b/util/uncompressedsize.py
index 6e9e44deb..5a6f16602 100644
--- a/util/uncompressedsize.py
+++ b/util/uncompressedsize.py
@@ -29,6 +29,7 @@ def backfill_sizes_from_data():
   has_images = bool(list(ImageStorage
                          .select(ImageStorage.uuid)
                          .where(ImageStorage.uncompressed_size >> None,
+                                ImageStorage.image_size > 0,
                                 ImageStorage.uploading == False)
                          .limit(1)))
 
@@ -43,6 +44,7 @@ def backfill_sizes_from_data():
     batch_ids = list(ImageStorage
                      .select(ImageStorage.uuid)
                      .where(ImageStorage.uncompressed_size >> None,
+                            ImageStorage.image_size > 0,
                             ImageStorage.uploading == False)
                      .limit(100)
                      .order_by(db_random_func()))