diff --git a/cross/media.py b/cross/media.py
index 928e2ec..dcbb99c 100644
--- a/cross/media.py
+++ b/cross/media.py
@@ -171,8 +171,9 @@ def get_media_meta(bytes: bytes) -> MediaInfo:
         raise ValueError("No video stream found")
 
     media: dict[str, Any] = cast(dict[str, Any], streams[0])
+    duration = media.get("duration", probe["format"].get("duration"))
     return MediaInfo(
         width=int(media["width"]),
         height=int(media["height"]),
-        duration=media.get("duration", probe["format"].get("duration")),
+        duration=float(duration) if duration is not None else None,
     )