MP4 to WEBM Converter
Convert MP4 to WEBM for free, right in your browser – no sign-up and no upload to a server.
Drop your file here
or click to browse
Supported formats: MP4, M4V · Max size: 500 MB
Your file stays on your device – it is never uploaded. Only convert files you own or have the right to use.
MP4 to WebM produces an open, web-optimised video file that browsers play natively – good for website backgrounds and short clips.
Large videos take a while – for long files pick the “Compressed” quality preset.
How to convert MP4 to WEBM
Choose a file
Drop your MP4 file into the box or click “Choose file”.
Click “Convert”
Conversion runs in your browser, so the file is never sent anywhere.
Download the result
You get a ready WEBM file – download it with one click.
MP4 vs WEBM: comparison
| Property | MP4 | WEBM |
|---|---|---|
| Compression | Lossy (H.264 / AAC) | Lossy (VP8/VP9) |
| Quality | Very good | Very good |
| File size | Small to medium | Small |
| Compatibility | Plays everywhere – phones, TVs, browsers, social networks | Great in browsers; limited on iPhone and older apps |
| Best for | Web video, social networks, sharing | Website video, short clips |
Why convert to WEBM
- Excellent browser support
- Small size at good quality
- Free and open format
Good to know about WEBM
- Not every app or device plays it
- Slower to encode than MP4
What is MP4 (H.264)?
The most universal video format. Web video, social networks, sharing.
What is WebM (VP8/VP9)?
An open Google video format designed for the web. Website video, short clips.
When to choose MP4 to WebM
WebM was designed for web video: most modern browsers play it, and files can be smaller than MP4. It is useful for short clips on websites, demos or animated backgrounds.
Common problems and fixes
- Conversion takes time – WebM encoding in a browser is slower than a simple MP4 remux, and long videos are better handled in desktop software.
- For a smaller file, choose a lower quality or a lower resolution (720p or 480p).
- Some Apple devices and older programs play WebM less well – if you will share the video with friends, MP4 may be safer.
- No audio – check that the original MP4 has an audio track.
Quality tips
First try a short clip to see the quality-to-size ratio before converting the whole file.