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INFORMATION & ANALYSIS · ON YOUR DEVICE

Video Duration Calculator

Read video length, convert timecodes and calculate a timestamp interval.

Ready to use

Opening local video workspace…

How to use Video Duration Calculator

  1. Choose a local video.

    Drop an MP4, MOV or WebM file, or choose one from your device. Playback depends on your browser’s codec support.

  2. Review the settings and supported scope.

    Read video length, convert timecodes and calculate a timestamp interval. Review the supported formats and limits before exporting.

  3. Inspect the result and save it.

    Run the action, inspect its output and download the result. For frame samples, the requested timestamps are included in filenames. Stream-copy tools report the actual output range and duration.

Supported formats

MP4, MOV, WebM → JSON / on-screen report

Limitations

  • MP4/MOV and WebM signatures accepted, up to 128 MiB. Native playback/frame tools require a browser-decodable video codec. Encrypted or damaged media is unsupported.
Are my files or recordings uploaded?

No. Video, subtitle text, filenames, metadata and generated frames stay in this browser. The host serves the application code and static assets. There is no conversion upload endpoint.

Does this convert every video codec?

No. This lightweight release uses native browser decoding and compatible encoded-stream copying. It does not use FFmpeg or fall back to full video transcoding. Unsupported media receives a clear error.

What does Experimental mean here?

The tool performs a real operation on verified inputs, but support across file variants, browsers and recording devices is incomplete. Review playback, timing and output before relying on it. Keep your original.

Keep working with your video