Subtitle Format Detector
Paste or load any subtitle content and see which format it appears to be — SRT, WebVTT or an unknown format — along with a confidence level and the reason for the match.
Local processing only. Content is inspected on your device. Nothing is uploaded.
Content to inspect
How format detection works
The detector inspects the content itself — not the filename — for format signatures:
- WEBVTT header on the first line indicates WebVTT.
- SRT timestamp pattern with a comma before milliseconds indicates SRT.
- VTT timestamp pattern with a period before milliseconds indicates WebVTT even without a header.
- SBV and ASS timing patterns are flagged as their own categories when detected.
Confidence levels
High — a definitive signature was found. Medium — the timing pattern matches but a header is missing. Low — the content has timing arrows but not in a supported format.