Read video metadata from a local MP4, WebM, or QuickTime file without uploading it to a server. The tool loads the file with an in-memory object URL, waits for loadedmetadata, and reports dimensions, duration, MIME type, and file size.
When to use it
- Verify export settings before publishing a clip
- Check resolution and aspect ratio for embed constraints
- Compare file size before and after compression elsewhere
How it works
The browser decodes container headers client-side. Width and height come from HTMLVideoElement.videoWidth / videoHeight; duration from video.duration. No frames are rendered or re-encoded.
Example
A 12.4 MB clip.mp4 at 1920×1080 with a 0:47 duration shows aspect ratio 16:9 and MIME video/mp4.
Limitations
- Codec and bitrate details are not exposed by the standard video element API
- Corrupt or DRM-protected files may fail to load
- Processing is limited to files up to 100 MB in the browser tab