Convert MP4 to WebM
Convert MP4 to WebM online free. Fast, private and in your browser — no upload, no sign-up and no watermark. Batch MP4→WebM conversion that works on any device.
To convert MP4 to WebM, drop your MP4 file into the converter above, then download the WebM result. It's free, needs no sign-up, and there's no watermark. Conversion runs in your browser with on-device FFmpeg, so your files never leave your device.
Why convert MP4 to WebM?
Convert MP4 to WebM for the web — VP9 in a WebM container gives smaller files at similar quality and is perfect for embedding video directly on a site with the HTML5 <video> tag.
- Embedding self-hosted video on a website.
- Reducing video weight for faster pages.
- Using an open, royalty-free format.
MP4 vs WebM
MP4 · MPEG-4 Part 14 (H.264)
MP4 with H.264 video is the most universally compatible video format — it plays everywhere and uploads cleanly to YouTube, Instagram, TikTok and messaging apps.
WebM · WebM (VP9)
WebM is an open, royalty-free format designed for the web. VP9 video gives smaller files than H.264 at similar quality and is ideal for embedding directly on a site.
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Video Converter
Convert video to MP4, WebM, MOV, MKV, GIF or MP3.
Open Video ConverterMP4 to WebM — frequently asked questions
How do I convert MP4 to WebM?
Drop your MP4 file (or several) into the converter, confirm WebM is selected as the output, click convert, then download the WebM file. The whole thing takes a few seconds.
Is this MP4 to WebM converter free?
Yes — it's completely free with no watermark and no sign-up required.
Is it safe to convert MP4 to WebM here?
Yes. Conversion runs on-device with FFmpeg compiled to WebAssembly, so your MP4 file is never uploaded to a server.
Can I convert multiple MP4 files at once?
Add your MP4 file and convert it, then repeat for the next one — each runs locally in your browser.
Does it work on mobile?
Yes — the converter runs in any modern browser on phones, tablets and desktops.