WebM to MP4 Converter: Convert WebM videos to MP4 where your browser supports it. Input: Video, MP4, WEBM, MOV, M4V, MKV files and values you enter. Output: Results shown on the page and a downloaded file. Privacy: Runs in your browser: inputs and files stay on your device and are not uploaded.
How to convert WebM to MP4
- Drop the .webm file.
- MP4 is selected if your browser can create it. If the format menu only offers WebM, try a current Chrome, Edge or Safari.
- Keep High quality and Original resolution, then click Convert and download.
Why MP4?
WebM (VP8/VP9 video) is common for screen recordings, browser downloads and web video, but some phones, editing apps, social networks and smart TVs only accept MP4 with H.264, the most compatible video format in the world. Converting gives you a file that plays almost anywhere.
The converter re-encodes the video with your browser's built-in codecs (the WebCodecs API), much faster than the video plays, and writes an MP4 with H.264 video and AAC sound. Browsers without WebCodecs record the video while it plays instead, which takes as long as the video. The result is re-encoded rather than copied, so keep High quality. Runs in your browser. Your files are not uploaded.
FAQ
Why can’t I choose MP4?
Your browser cannot encode MP4. Use Safari or a recent Chrome or Edge.
Will the quality change?
Slightly, because the video is re-encoded. Use High quality and Original resolution.
Is there a length limit?
No fixed limit; long videos need enough device memory. With WebCodecs it converts much faster than the video plays.