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Subtitle Converter

Convert any subtitle file between SRT, VTT, SBV, and plain text. The format is detected automatically, and the conversion runs in your browser — your file is never uploaded.

100% private: files are processed in your browser and never uploaded.

Want to do more with your subtitles?

Need to edit subtitles against the video, transcribe, translate, or burn captions into the video itself? Captioner is a full subtitle editor with AI transcription in 100+ languages, translation, and styled caption rendering.

Open in the Captioner editor

How it works

  1. Step 1

    Drop any .srt, .vtt, or .sbv file into the box — the source format is detected automatically.

  2. Step 2

    Pick the output format: SRT, VTT, SBV, or plain text. Switching re-converts the same file.

  3. Step 3

    Your renamed file downloads instantly, converted entirely in your browser.

Frequently asked questions

Which subtitle formats can I convert?
SRT (SubRip), VTT (WebVTT), and SBV (YouTube) in any direction, plus plain text (.txt) output for transcripts. The input format is detected automatically from the file contents.
How does the converter work without uploading my file?
Everything runs as JavaScript in your browser: the file is read locally, parsed into cues, and rebuilt in the target format on your device. You can watch the network tab — no requests are made during conversion.
Is there a file size or conversion limit?
No. Because the conversion happens on your device there are no quotas, accounts, or watermarks. Even feature-length subtitle files convert instantly.
Will timing stay accurate after conversion?
Yes. Cue start and end times are preserved with millisecond precision, and cue order and line breaks are kept exactly as in the source file.
Does it handle Chinese, Cantonese, Japanese, or Korean subtitles?
Yes. Files are processed as UTF-8 throughout, so CJK text, full-width punctuation, and mixed-language subtitles convert without corruption.
What happens to formatting tags like italics?
Italic and bold tags are kept when converting between SRT and VTT, which both support them. SBV and plain text do not support markup, so tags are stripped cleanly for those outputs.

More free subtitle tools

See all subtitle tools or check Captioner pricing.