Convert WebM to MP4.
WebM to MP4 converted on your device — files never leave.
Drop WebM files here
or browse your files
Paste with ⌘V · or drop files anywhere on the page
Files never leave your device. Everything runs in your browser, nothing touches a server — tools you've used even work offline.
Turn WebM videos into MP4 without uploading them — the whole conversion happens in your browser. WebM plays great in browsers, but Apple devices, TVs, and most editors still want MP4. Drop a batch, keep the audio, and download files that play everywhere.
How it works
- Drop files anywhere on the page, click to browse, or paste with ⌘V.
- Pick a quality or preset — or set an exact target size and let the tool find it.
- Compress, compare before/after, and download — individually or as a ZIP.
Where WebM refuses to play
WebM was built for browsers, and there it is excellent — but step outside and support thins fast: iPhones and iPads, Apple TV and many smart TVs, video editors, office software and upload forms all expect MP4. Converting once to MP4 with H.264 ends the compatibility guesswork.
Screen recordings are the classic case
Screen recorders that run in a browser — meeting tools, recorder extensions — save WebM, because that is the format browsers record natively. Convert the recording to MP4 and it drops into every editor, deck and chat app; if it also needs to be smaller, Compress MP4 takes it from there.
Frequently asked questions
Why convert WebM to MP4?
WebM is a web-first format — iPhones, iPads, Apple TV, many smart TVs and video editors cannot open it. MP4 with H.264 plays essentially everywhere.
Does the video lose quality?
One re-encode happens, right on your own device. At the default quality the difference is not visible in normal viewing; raise the slider if you want extra headroom.
Is the audio kept?
Yes — the audio track is carried over or converted as needed for MP4 playback. If your browser cannot manage it, the tool warns you instead of failing silently.
Do my videos get uploaded?
No. Encoding runs on your own hardware from first frame to last — nothing streams to a server, which is also why there is no file-size cap and no queue. Close the tab and every trace of the footage is gone. Want proof? Run one file through, switch your connection off, and run another — it still works.