Converters Video
MOV, MKV, AVI and WebM into MP4, converted on your own machine.
Your files stay on your device. The tool works directly in your browser, using your device to process your files. Nothing is sent to our servers, and we never receive, store, or see your files or figures.
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Video converter
Convert MOV, MKV, AVI, WebM and MP4 in any direction, with the whole conversion running inside your browser.
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MOV to MP4
Turn iPhone and QuickTime MOV files into MP4, usually without re-encoding a single frame.
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MKV to MP4
Convert Matroska MKV files to MP4 in seconds, copying the video across rather than re-encoding it.
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AVI to MP4
Bring old AVI footage from camcorders and 2000s-era files into MP4 that modern devices will actually play.
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WebM to MP4
Convert WebM recordings and downloads to MP4 so phones, editors and social platforms will accept them.
Nothing here is uploaded
Every other free video converter works the same way: your file goes to their server, waits in a queue, gets converted, and you download the result. That means a copy of your video sitting on a machine you do not control, governed by a privacy policy you did not read. For a holiday clip that may not matter. For a recorded meeting, a medical scan, a client's footage or anything filmed inside your home, it matters a great deal.
These tools run FFmpeg compiled to WebAssembly inside your own browser tab. The engine is a 9.8 MB download the first time you convert something, and it is kept afterwards, so the second conversion starts instantly. Your video is read from disk, converted in memory and written back to your downloads folder. It never touches the network.
Most conversions do not re-encode anything
A container, meaning MP4, MOV, MKV or AVI, is a wrapper. The picture inside it is a separate thing, encoded with a codec such as H.264. A phone, a camera and a screen recorder all produce H.264 inside whatever container their maker preferred, which is why "convert MOV to MP4" is usually a matter of rewriting the wrapper and copying the picture across untouched.
Every video tool here tries that first. When it works you get an exact copy in seconds, with no quality lost and no settings to get wrong, and the tool tells you it happened. When the codec genuinely cannot live in the target container, as VP9 from a WebM has no place in an MP4, it falls back to a real re-encode, which is slower and does cost a generation of quality.
Which format should you convert to?
| Target | Choose it when |
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| MP4 | Almost always. It plays on every phone, TV, browser and editor made this century, and it is what every social platform wants uploaded. |
| WebM | You are putting the video on your own website and want the smallest file. Requires a re-encode from anything, so it is slow. |
| MKV | You are archiving and want subtitles, chapters and several audio tracks kept intact. |
| MOV | Final Cut Pro or an older Apple workflow has asked for it specifically. |
| GIF | A short silent loop for a chat or a bug report. Expect a large file for a few seconds. |
How long it takes
A stream copy runs at disk speed: a 500 MB file takes a few seconds. A re-encode is bound by your processor, and the engine runs on a single core, so budget roughly one to three minutes per minute of video on a laptop and rather longer on a phone. Lowering the resolution shortens it considerably, because there are simply fewer pixels to compress.
