Free tool · JSONSBV

Convert JSON
to SBV

Drop in a .json (JSON cue array) file, get a clean .sbv (SubViewer / YouTube SBV) back. SubViewer / YouTube SBV is a minimal subtitle format YouTube's uploader accepts — comma-separated timestamps, no cue numbers. The conversion runs entirely in your browser — your captions never leave the page.

Input · JSON
Output · SBV
Everything runs in your browser — no upload, no signup.
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Frequently asked

Why convert JSON to SBV?+

JSON cue array is a structured array of `{ index, start, end, text }` objects — clean for any captions pipeline. SubViewer / YouTube SBV is built for legacy YouTube uploads and SubViewer-compatible players. Converting lets you take a file produced for one workflow and use it in the other without re-typing or re-timing anything.

Is timing preserved exactly?+

Yes. The converter only re-encodes the file structure — start and end times round-trip to within one millisecond.

Does any styling survive the conversion?+

Neither format carries styling, so there's nothing to lose. The text and timing transfer exactly.

Does this run on a server?+

No. The conversion is pure JavaScript running in your browser — files never upload anywhere. Works offline once the page is loaded.

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