WebM to MP4
To convert WebM to MP4, choose the WebM file and press Convert. "Most compatible" re-encodes to H.264/AAC for every device; "Fastest" puts the VP9/Opus streams into MP4 without re-encoding.
- ๐ Runs on your device
- โค 0 bytes uploaded
- ๐ด Works offline
- โ Free, no sign-up, no watermark
- โฌ 0.7 MB engine, first use only
How to use WebM to MP4
- Choose your WebM videos.
- Pick "Most compatible" (H.264) or "Fastest" (no re-encode).
- Press Convert.
- Download the MP4.
Is it private?
Yes. WebM to MP4 runs entirely in your web browser using your device's own processor. Your files are never uploaded to Nolo or anyone else, and the page cannot send them anywhere: its security policy only allows it to talk to nolotools.com, which has no place to receive files. Results are kept encrypted on your device for 60 minutes in Your files, then deleted automatically, or straight away with Delete all. How Nolo works.
Questions and answers
Are my videos uploaded?
No. Everything happens inside your browser with its built-in media engine (WebCodecs). Your videos never leave your device, and the page works offline once loaded.
Why convert WebM to MP4?
WebM is great on the web, but many editors, phones, TVs and messaging apps expect MP4 with H.264. Converting makes the video play everywhere.
Which option should I choose?
"Most compatible" for sharing and editing. "Fastest" if you only need an .mp4 file for a modern browser or VLC; it is instant but keeps VP9 video.
My browser says it cannot encode H.264. What can I do?
Some browser builds (for example on Linux) have no H.264 encoder. Use "Fastest", or open the page in Chrome or Edge on Windows, macOS or Android.
Is there a limit?
No limit from Nolo. Long high-resolution videos take a while to re-encode and need enough free memory.