Convert video to MP4
Turn a MOV, MKV, WebM, M4V or TS video into a widely-compatible MP4 in your browser — H.264 and AAC for maximum compatibility, or a fast lossless remux when the source codecs already fit. Nothing is uploaded and there is no file-size limit.
Open Convert video to MP4 →Convert video to MP4 online — free and private
MP4 is the format that plays everywhere: every phone, every smart TV, e-mail previews and office software. This converter turns MOV, MKV, WebM, M4V and MPEG-TS files into MP4 entirely inside your browser, on the WebCodecs engine. Best compatibility re-encodes to H.264 video and AAC audio, the safest pairing there is. Fastest instead copies any track the MP4 container can already hold — an instant, lossless remux that only rewrites the container. The same tool also writes WebM, MKV and MOV if you need one of those instead.
How to use Convert video to MP4
- Add your video — Drag a MOV, MKV, WebM, M4V or TS file onto the drop zone, or click to browse. The tool reads its container, resolution and codecs and shows them immediately.
- Pick MP4 and a mode — MP4 is the default output. Keep Best compatibility for H.264 and AAC, or switch to Fastest when you only need the container changed.
- Convert and download — Watch the progress, preview the result, and save the .mp4 file.
Frequently asked questions
Is my video uploaded to a server?
No. The conversion runs in your browser with WebCodecs, on your own device. It works offline and has no file-size limit.
When is the conversion lossless?
In Fastest mode, when the source tracks already use codecs MP4 can hold — H.264, HEVC, AV1, AAC, MP3 and so on are copied byte for byte and only the container changes. A WebM carrying VP8 and Vorbis has to be re-encoded.
Why H.264 and AAC?
It is the most universally supported pairing. Older smart TVs, PowerPoint, e-mail previews and every phone play it, whereas newer codecs make smaller files but still meet players that refuse them.
Can it convert AVI, WMV or FLV?
No, and neither can any other in-browser converter — browsers have no decoder for those containers. The tool says so plainly rather than failing silently. MP4, M4V, MOV, MKV, WebM and MPEG-TS all work.