diff --git a/backend/app/routes.py b/backend/app/routes.py
index 39281e7..381e1d7 100644
--- a/backend/app/routes.py
+++ b/backend/app/routes.py
@@ -2739,7 +2739,7 @@ def check_consistency(
                 if len(missing_s3_keys) < limit:
                     missing_s3_keys.append(artifact.s3_key)
             else:
-                s3_size = s3_info.get("ContentLength", 0)
+                s3_size = s3_info.get("size", 0)
                 if s3_size != artifact.size:
                     if len(size_mismatches) < limit:
                         size_mismatches.append(