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SUBTITLES · ON YOUR DEVICE

Subtitle Time Shifter

Advance or delay SRT and WebVTT cues, preview timing changes and handle negative starts explicitly.

Ready to use

How to use Subtitle Time Shifter

  1. Open your subtitle text.

    Drop a UTF-8 SRT or WebVTT file, or paste cues into the text editor. The validation report updates locally.

  2. Review the settings and supported scope.

    Advance or delay SRT and WebVTT cues, preview timing changes and handle negative starts explicitly. Review the supported formats and limits before exporting.

  3. Inspect the result and save it.

    Review cue timing and warnings, then generate a UTF-8 file. Invalid timing must be fixed before export.

Supported formats

SRT, WebVTT → SRT, WebVTT

Limitations

  • UTF-8 SRT/WebVTT up to 2 MB. Advanced WebVTT notes/styles/regions are not preserved; positioning is retained only in WebVTT output. Malformed cues must be corrected before export.
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