More subtitles tools
Your files never leave your device
This is not a promise about how carefully we handle your upload. There is no upload. The file you choose is read into memory by your own browser, processed there, and handed back as a download — the tool has no server component and makes no network request with your data.
- Nothing is stored. We never receive the file, so there is no copy to retain, no retention period to disclose, and nothing to delete on request.
- Nothing is transmitted. No upload endpoint, no analytics payload carrying file contents, no third-party processor.
- You can verify it. Load this page, disconnect from the internet, and use the tool. It still works, because everything it needs is already on your machine.
- Nothing persists after you close the tab. Files are held in page memory only — not in local storage, not in a cache, not in a database.
A note on wording, because it matters: we do not describe these tools as “encrypted.” Encryption protects data that travels to somebody else's computer. Your file does not travel, so there is nothing to encrypt and nothing to intercept — which is a stronger guarantee than encryption, not a weaker one. The page itself is served over HTTPS like the rest of the site.
This makes the tools safe for material you are contractually barred from uploading to third-party services — client footage under NDA, unreleased campaign assets, anything covered by a confidentiality clause.
Questions
My captions drift further out as the video goes on. Will this fix it?
No, and it is worth knowing why. A constant offset fixes a track that is uniformly early or late. Progressive drift means the caption track and the video are running at different frame rates — a 25fps track against 23.976fps footage, typically — so the error grows with time. That needs the timings rescaled, not shifted.
What happens to cues that would end up before zero?
They are clamped to 00:00:00 rather than dropped or given a negative timestamp, which most players either reject or render unpredictably. If several cues clamp, your offset is larger than the gap at the start of the file.
Do my files get uploaded anywhere?
No. This tool runs entirely in your browser using the Canvas and File APIs. The file you choose is read into memory on your own machine, processed there, and offered back as a download. Nothing is sent to a server, which is also why it keeps working with your network off.
Is it actually free, or is there a catch?
Actually free, with no account and no limit, because it costs nothing to run — the work happens on your device rather than on our hardware. That is different from generating with an AI model on Versely, which does cost credits; there is no free tier for generation.
These rearrange files. Versely makes new ones.
Everything on this page works on a file you already have, which is why it costs nothing. Generating something that did not exist — video from a prompt, a voice, a score — runs a model, and that costs credits.