Caption Checkby Small Fixes LabFiles stay in your browser

Subtitle review desk

Check SRT and WebVTT timing, reading speed and format before delivery.

Source

Review thresholds

Set these to your delivery brief. Warnings need your judgement.

Original files are never rewritten.

Example report

Choose a file or try the sample to begin.

Cue timing

Intervals from the subtitle file

● Cue ● Review ● Error

Select a cue to inspect its text and findings. No audio or video alignment is checked.

Reports include all findings and subtitle excerpts, even when this view is filtered.

Choose a file, paste text or use the example to see findings here.

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What the report tells you

Format errors flag problems such as broken timestamps, empty cues and invalid sequence numbers. Findings are grouped by cue, with reported source lines and the original cue block.

Review warnings flag overlaps, reading speed, line length and duration. An overlap may be intentional. Use your language and delivery requirements to decide what to change.

The checker leaves your files unchanged. It does not check audio alignment, translation or acceptance by a particular platform.

Privacy and file handling

Subtitle text is processed in this browser. The checker does not upload your files, use analytics cookies or store them between visits. Clear the page or close the tab to remove the current results.

Downloaded reports contain excerpts from your subtitles. Keep them as private as the source files.

The public site is hosted by Cloudflare, which processes ordinary connection information such as your IP address to serve and protect the site. Its privacy policy covers that processing. The offline edition makes no network requests to check files.

If you email us for help, your email and anything you choose to send are handled in our support inbox. You can ask us to delete that correspondence at hssilmoon.00@gmail.com. This note was updated on 6 September 2026.