Video Metadata Viewer
View duration resolution and codec info of a video
Updated
What is the Video Metadata Viewer?
Inspect any video file instantly in your browser. The Video Metadata Viewer extracts duration, resolution, codec inference, container format, audio/video track details, and estimated bitrate — 100% client-side with zero uploads. Drag and drop MP4, MOV, MKV, AVI, WEBM, FLV, M4V, or WMV files and see structured results in seconds. Perfect for content creators, developers, editors, and anyone who needs quick technical video specs without installing heavy tools.
How it works
The tool uses native browser APIs (HTMLVideoElement) to read file-level and stream-level metadata directly from the video container. When you drop or select a file, it creates a temporary object URL and loads it into a hidden/preloaded video element. Once loadedmetadata fires, the browser exposes duration, width, height, video tracks, and audio tracks. The pure utility layer (utils.ts) formats these raw values, infers container and codec from MIME types and file extensions, calculates aspect ratios with GCD simplification, estimates bitrate from file size divided by duration, and structures everything into clean JSON or readable cards. No server, no external library, no privacy risk.
Examples
Inspect a 4K MP4
Drop a high-resolution MP4 to read its 3840x2160 resolution, H.264 codec inference, 30.2 Mbps bitrate, and 2 audio tracks.
Analyze a MOV file
Check a QuickTime MOV for ProRes codec hints, track selection, and estimated size-based bitrate.
Frequently asked questions
Does the Video Metadata Viewer upload my files?
Does the Video Metadata Viewer upload my files?
No. Every operation happens locally inside your browser using the native FileReader, URL.createObjectURL, and HTMLVideoElement APIs. Your video never leaves your device.
Which video formats are supported?
Which video formats are supported?
The viewer accepts any file the browser's media engine can parse: MP4, MOV, MKV, AVI, WEBM, FLV, WMV, M4V, OGV, TS, MTS, VOB, and more. If the browser can load it, the metadata viewer can read it.
What metadata does it show?
What metadata does it show?
Duration, resolution (width × height), aspect ratio, container format, inferred codec string, file size, MIME type, estimated bitrate (bps/kbps/Mbps), video track count and selection status, audio track count with language and enabled status, and a formatted timestamp of last modified.
Why does the codec show "inferred"?
Why does the codec show "inferred"?
Browsers do not always expose the exact codec string through JavaScript APIs. The tool reads the codecs= parameter from the MIME type when present, and falls back to common mappings based on container (e.g., MP4 → H.264/AAC). It is clearly labeled as inferred.
Can I export or copy the results?
Can I export or copy the results?
Yes. The overview mode includes a "Copy JSON" button and "Download JSON" / "Download Report" buttons. The raw mode lets you copy the formatted JSON directly.
Is there a file size limit?
Is there a file size limit?
No artificial limit. The only constraints are your browser's memory and the time required to read metadata from very large files (preloading uses preload="metadata" for speed).
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