Convert Video
Change a video's format without uploading it — the encoder is downloaded to you instead.
Free No signup Runs in your browser — nothing uploaded
What it does
Convert Video reads the whole document before doing anything, so what comes back is either valid output or a specific error with the position that caused it — not a partially rewritten file.
When you need it
Usually when something has already gone wrong: a config file an application will not load, an API response that has to be read by a human, or an export that has to be checked before it goes anywhere near a database.
Limits and caveats
Key order is preserved as it appears in the input. Very large documents are limited by your device's memory rather than by an upload cap, since the parsing happens locally. Everything happens in your browser, so the file never leaves your device.
How to convert video
- Drop the video. Nothing is uploaded.
- Pick a format and a quality.
- Wait — encoding in a browser is slower than a desktop app — and download.
Frequently asked questions
- Why is there a 32 MB download the first time?
- That is ffmpeg, compiled to WebAssembly. Every other free converter runs it on their server, which means your video goes there. This runs it on your machine, and the cost of that is fetching the encoder once. It is cached afterwards.
- Why is it slower than my desktop app?
- Because a browser tab cannot use your machine the way a native binary can — no hardware encoder, one thread. For a clip it is a fair trade for not uploading anything. For a two-hour recording it is not, and a desktop tool is the right answer.
- How big a file can it handle?
- Everything happens in memory, so the practical ceiling is a few hundred megabytes before the tab runs out. If it fails on a large file, trim it first.
- Do my files get uploaded?
- No. This tool runs entirely in your browser, so the file never leaves your device.