Subtitle Converter — SRT, VTT, ASS and Plain Text
Drop in a caption file and get it back in the format the platform you are posting to actually accepts. Conversion happens in your browser, so the transcript, which is often the most sensitive part of a recording, never leaves your machine.
Which format goes where
Caption formats are not interchangeable, and picking the wrong one usually means an upload silently rejected or captions that do not appear at all.
- SRT is the universal default — YouTube, Vimeo, Premiere, DaVinci Resolve and most social platforms accept it
- VTT is the web standard, required by the HTML5 track element and most in-browser players
- ASS carries styling and positioning, which matters for anime fansubs and karaoke but is stripped by most platforms
- TXT is the plain transcript, useful for show notes, blog posts and search indexing
What survives a conversion and what does not
Timing survives every conversion. Styling does not. Converting ASS to SRT discards fonts, colours and on-screen positioning because SRT has no way to express them, and converting SRT to ASS cannot invent styling that was never there. Going to plain text drops timing entirely, which is what you want for show notes and wrong for anything that has to stay in sync.
How to use it
- Load your caption file. Open the Subtitle Converter and select your existing SRT, VTT or ASS file.
- Choose the output format. Pick the format the destination platform expects.
- Download the converted file. The converted captions save straight to your device with timings intact.
Frequently asked questions
Why will YouTube not accept my VTT file?
YouTube prefers SRT, and some VTT files carry header or styling blocks that its importer rejects. Converting to SRT strips those extras and usually resolves the upload.
Will converting break my caption timings?
No. Timings are preserved across SRT, VTT and ASS. Only conversion to plain text discards them, because plain text has no timing concept.
Can I convert a transcript back into timed captions?
Not from plain text alone — the timing information is gone once it is dropped. You would need to re-transcribe the audio, which the AI subtitle generator can do.
Related tools
- AI Subtitle Generator — Auto-generate SRT captions with Whisper running on your own device.
- Transcript Summarizer — Turn transcripts into descriptions, newsletters and posts.
- Video Compressor — Shrink video file size locally with FFmpeg — no upload, no watermark.