Free WebM to MP4 Converter
Convert WebM videos to universally compatible MP4 format in seconds.
Upload your WebM file and get an H.264 MP4 that works on every device and platform.
Drop your WebM file here
or click to browse • .webm files only
Editing is a pain in the ass, right?
That's why we're building Cubix. No more editing hell.
AI Video Editor
Drop your footage, tell it what you want. Cubix cuts, captions, color grades, and exports — fully on its own. No timeline. No manual work. Just results.
Cinematic Screen Recorder
Hit record on Windows. Auto-zoom, cinematic backgrounds, and studio-quality audio kick in automatically — your screen recording looks edited before you've touched a thing.
Universal MP4
H.264 + AAC output plays on every device — iPhone, Android, Windows, Mac, smart TVs, and all media players.
Fast Conversion
Server-side FFmpeg processing delivers quick conversions. Upload, convert, and download in minutes.
Preview First
Preview the converted MP4 directly in your browser before downloading to make sure everything looks right.
Frequently Asked Questions
Is the WebM to MP4 converter free?
Yes. Convert WebM videos to MP4 for free with no signup, no watermark on downloads, and no software to install.
What output settings are used?
Output uses H.264 video codec with CRF 23 quality, AAC audio at default bitrate, and the faststart flag for web playback optimization.
Why convert WebM to MP4?
WebM is primarily supported by Chrome-based browsers. MP4 with H.264 is universally compatible with virtually all devices, platforms, and media players.
Is there a file size limit?
No fixed limit is imposed by this tool, but very large files will take longer to process.
Will converting affect quality?
The conversion re-encodes the video. With CRF 23, quality is good and output size is typically similar to or smaller than the source WebM.
Related video tools
Subtitles, trim, merge, MOV/MP4 converters, and more.