WebM to MP4 Converter

Convert WebM files to MP4 without uploading them. Everything runs on your own device.

Choose a video

Browse files

or drag and drop · MP4, MKV, AVI, WebM, MOV — up to 1GB

Processed on your device. This file is never uploaded.

  1. 1Drop your WebM file into the box above — it stays on your device.
  2. 2MP4 is already selected as the output, so there is nothing to configure.
  3. 3Download the converted MP4 file.

Converting WebM to MP4

This page is the WebM to MP4 setting of our converter, with MP4 already chosen. Drop a WebM file in and the result comes back as MP4 — no account, no queue, and no watermark on the output.

The conversion runs entirely inside your browser tab. Your file is read into memory on your own machine, converted there, and handed straight back. Nothing is uploaded, which means there is no size limit imposed by someone else's bandwidth and no copy of your file sitting on a server after you close the tab.

What is WebM?

Open and royalty-free, built for the web. Smaller than MP4 at similar quality, and noticeably slower to encode.

What is MP4?

H.264 in an MP4 container. Plays on effectively every device made this century, and the right default for sharing.

What changes in this conversion

This is a full re-encode: every frame is decoded and compressed again. In the browser that runs far slower than native software, so expect minutes rather than seconds on a long clip.

Is it really free?

Yes, and there is no catch to explain. Because the work happens on your device rather than on a server, running this costs us nothing per conversion — so there is no bill to recover and nothing to gate behind a sign-up, a daily quota or a watermark.

Frequently asked questions