Subtitle Tools

Parse and convert SRT/VTT subtitles locally, with support for global time shifting, merging, and time-overlap checks.

Local browser processing
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User Guide

How to use the subtitle tool

The subtitle tool processes input only in the current browser; it does not upload, connect to the internet, or save user data.

  1. Input content

    Paste or load subtitle files no larger than 5 MiB in SRT/VTT format.

  2. Select a processing method

    Select the input and output formats, millisecond offset, and optional second subtitle.

  3. Check and export

    View line numbers and cue errors, reparse and validate, then copy or download the subtitles.

Limitations and Notes

  • Up to 100,000 cues; audio is not parsed, speech recognition is not performed, and FFmpeg is not loaded.
  • Blank lines, overlaps, and time offsets may change the player display; verify them in the target player before downloading.
  • The tool only provides locally processed results; important configurations, secrets, documents, and published content must still be reviewed in the target environment.

FAQ

Will the input be uploaded to a server?

No. The page only uses browser memory, the local file API, and local resources already provided with the site.

Can the tool automatically generate subtitles from audio?

No. It only processes existing SRT/VTT text; it does not read audio or perform speech recognition.

Why do the results still require manual review?

Edge-case syntax, regional standards, third-party readers, and target runtime environments may differ; the tool does not replace final validation.

Page feedbackFound an issue or have suggestions for improvement?
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