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WebM to MP4

Convert a WebM video — from a browser screen recorder, a web download or a chat app — into an MP4 that plays in editors, on iPhones and on upload forms.

WebM to MP4

Browser recordings → MP4

  1. Choose
  2. Process
  3. Download

Drop a file here, or click to choose

Up to 100MB · nothing is uploaded until you press Run

Up to 100MB

About this tool

This converts a WebM video into an MP4. WebM is the open web format: browser screen recorders, some chat apps and many web downloads produce it. Browsers play it, but many editors, Apple apps and upload forms do not accept it. The MP4 you get back uses H.264 video and AAC audio and plays essentially everywhere.

How to convert WebM to MP4

  1. 1.Choose the WebM file.
  2. 2.Press Run and leave the tab open while it converts.
  3. 3.Download the MP4.

When people use it

Browser screen recordings

Turn a recording from a browser extension or web app into an MP4 you can edit or send.

Editing software

Many video editors import MP4 reliably and WebM badly or not at all.

Sharing with iPhone users

An MP4 opens in the iPhone's built-in apps.

What it will not do

Worth knowing before you upload, rather than after.

  • The video is re-encoded to H.264, which takes a little time and can make the file larger than the WebM.
  • A damaged or cut-off recording, such as one from a browser tab that crashed, may fail to convert.
  • Free files are limited to 100MB and 20 minutes.

Questions

How do I convert WebM to MP4?

Choose the WebM file above and press Run. Download the MP4 when it finishes.

Does it work with browser screen recordings?

Yes. Browser recorders often write WebM files that do not store their length. We measure the length when we read the file, so these convert like any other WebM.

Will the MP4 be bigger than the WebM?

It can be. WebM usually carries VP9 video, which compresses efficiently. H.264 trades some file size for compatibility.

Is it free?

Yes — free, no account, no watermark, for files up to 100MB and 20 minutes long.

What happens to my file?

Your upload goes to private storage that is never public and never listed, and only the anonymous session that created the job can read it. The original file is deleted as soon as processing succeeds. The result stays available for about 90 minutes, and you can delete everything immediately with the Delete now button.

More conversions

Other tools

Want bigger files, several at once, or no queue? See Pro.