Convert WebM to MP4
Fast, free, and completely private. Your videos are converted right here in your browser — no uploads, no watermarks, no waiting in line.
Drop your WebM files here
or click to browse. Convert as many files as you like — all in your browser.
100% Private
Files are converted locally in your browser. Nothing is ever uploaded to a server.
No Limits
No file size caps, no watermarks, no sign-up. Convert as many videos as you want.
Works Offline
Once the page loads, conversion runs entirely on your device — no connection needed.
High Quality
Powered by FFmpeg with H.264 + AAC encoding for broad compatibility and crisp output.
How it works
- 1Drop or select one or more .webm files.
- 2The converter runs locally in your browser and shows live progress.
- 3Download your ready-to-use MP4 files — that simple.
Frequently asked questions
- Is my video uploaded anywhere?
- No. This converter uses WebAssembly (FFmpeg compiled for the browser), so your files are processed entirely on your own device. They never leave your computer.
- Is there a file size limit?
- There is no hard limit imposed by us. Because conversion happens in your browser, the practical limit depends on your device memory. Very large files may take longer or require a desktop browser.
- What formats does the output use?
- Your WebM video is converted to an MP4 file using the H.264 video codec and AAC audio, which plays on virtually every device, browser, and editor.
- Is it really free?
- Yes, completely free with no watermarks, no account, and no ads interrupting your conversion.