MP4 to WebM Converter
Convert MP4 video files to WebM format directly in your browser using VP8/VP9 — no upload, no server, completely private.
Convert MP4 to WebM
100% client-side — your video never leaves your device.
Need faster conversion? Use FFmpeg
For large files or batch conversion, FFmpeg is much faster than the browser.
# VP9 (best quality/size)
ffmpeg -i input.mp4 -c:v libvpx-vp9 -b:v 0 -crf 30 output.webm
# VP8 (fast)
ffmpeg -i input.mp4 -c:v libvpx -c:a libvorbis output.webm
ffmpeg -i input.mp4 -c:v libvpx-vp9 -b:v 0 -crf 30 output.webm
# VP8 (fast)
ffmpeg -i input.mp4 -c:v libvpx -c:a libvorbis output.webm
Source Video
No video selected yet
Conversion Progress
Starting...
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Conversion plays the video in real-time. Duration matches the video length.
Converted WebM Output
Download WebMSummary
Convert MP4 video files to WebM format directly in your browser using VP8/VP9 — no upload, no server, completely private.
How it works
- Select or drag an MP4 video file onto the drop zone.
- Choose your preferred output codec: VP8 (faster, wider support) or VP9 (better compression).
- Click "Convert to WebM" to start the client-side conversion using MediaRecorder.
- A progress indicator shows conversion status as frames are captured.
- When complete, click "Download WebM" to save the converted file to your computer.
Use cases
- Prepare video files for web embedding without re-uploading to a server.
- Convert MP4 recordings to WebM for use in HTML5 video tags.
- Reduce video file size using VP9's efficient compression for web delivery.
- Convert screen recordings or tutorials to a web-friendly format.
- Create WebM files for use in web applications that require open formats.
- Convert videos privately without exposing footage to third-party services.
Frequently Asked Questions
Last updated: 2026-06-11 ·
Reviewed by Nham Vu