Convert WebM to MP4
To convert WebM to MP4, pick the WebM file and press Convert to MP4. The video is re-encoded to H.264 and the sound to AAC, which is the combination that plays on iPhones, TVs and in every editor.
Drop a WebM video here
or
WEBM
Up to 2 GB on a computer and 1 GB on a phone, because your device does the work. You can also paste a file.
Stays on your device
Your file is never uploaded
Up to 2 GB
On a computer
MP4 out
Ready to download
How it works
- To convert WebM to MP4, pick a WebM file, such as a browser screen recording.
- The tool decodes the VP8, VP9 or AV1 video inside it.
- It re-encodes the video to H.264 and the sound to AAC. This is a real conversion, so it takes longer than a simple copy.
- The bitrate is set a little above the original so the picture looks the same.
- Download the MP4.
Facts
- Where it runs
- In your browser, on your device. Nothing is uploaded
- Input format
- WebM with VP8, VP9 or AV1 video
- Output format
- MP4 with H.264 video and AAC sound
- Re-encoding
- Always. WebM and MP4 use different video and sound formats, so a plain copy is not possible
- File size
- Usually a little larger than the WebM, to keep the same look
- Max file size
- 2 GB on a computer, 1 GB on a phone
- Browsers
- Chrome and Edge 94 or later, Safari 16.4 or later, Firefox 130 or later on a computer
Questions
How do I convert WebM to MP4?
Pick the WebM file on this page and press Convert to MP4. Your browser re-encodes it to H.264 video and AAC sound, and you download the MP4 when it is done.
Why will my WebM file not play on my iPhone or TV?
WebM uses the VP8, VP9 or AV1 video formats, which many phones, TVs and video editors do not support. MP4 with H.264 plays almost everywhere.
Does converting WebM to MP4 lose quality?
A little, because the video has to be re-encoded. The tool uses a slightly higher bitrate than the original to keep the difference hard to see.
Why is the MP4 larger than the WebM?
VP9 and AV1 pack video more tightly than H.264. To look the same, H.264 needs more data, so the MP4 is often somewhat larger. You can shrink it afterwards with the video compressor.