How do I convert a WebM video to MP4?
To convert WebM to MP4, open FixDoks's WebM to MP4 tool, select the .webm file, choose a quality level such as Balanced, then click Convert to MP4. The tool re-encodes VP8 or VP9 video to H.264 and Opus audio to AAC in your browser, so nothing is uploaded, and the MP4 plays on iPhone, Windows and smart TVs.
WebM to MP4 at a glance
| Input | WebM (VP8/VP9 + Opus/Vorbis), up to 200 MB |
|---|---|
| Output | MP4 (H.264 + AAC) |
| Processing | In your browser; your files are not uploaded |
| Price | Free, no watermark |
| Download | Free Google sign-in |
| Works on | Chrome, Edge, Safari and Firefox on Windows, Mac, Android and iPhone |
How to use WebM to MP4
- Click Select video and choose a .webm file up to 200 MB.
- Choose a quality level. Balanced is right for most videos.
- Click Convert to MP4 and download the result.
What is WebM and why convert it?
WebM is an open video format created for the web. It uses the VP8 or VP9 video codec with Opus or Vorbis audio. Browsers love it, and it is what Chrome, Firefox and many screen recording tools produce by default. The trouble starts when you leave the browser: older versions of Windows Media Player, many smart TVs, some video editors, and messaging apps on iPhone either refuse WebM or play it without sound.
MP4 with H.264 video and AAC audio is the one format that plays everywhere. Converting takes a WebM file and re-encodes it into that universal combination.
Common reasons people convert WebM
- Screen recordings. Browser based recorders, including the one on FixDoks, often save WebM. Converting lets you upload to platforms that expect MP4 or edit in apps like iMovie.
- Sharing to iPhone users. iOS support for WebM is limited, especially in messaging apps.
- Video editors and presentation software. Many only import MP4 or MOV.
- Upload forms. Job portals, course platforms and government sites often list MP4 as the only accepted video type.
Quality and speed
VP9 and H.264 are different codecs, so the video has to be decoded and encoded again. The Balanced setting keeps the picture visually the same as the source. High quality is useful for recordings with small text, such as code or spreadsheets. Encoding runs on your device, so a few minutes of 1080p footage can take a few minutes to convert. Short clips are quick.
Audio is converted from Opus or Vorbis to AAC at 160 kbps stereo, which is transparent for speech and music. If the WebM has no audio, the MP4 is silent too.
Making the file smaller at the same time
If the converted MP4 is still too large to send, run it through Compress Video to lower the resolution or set an exact target size. If you only need part of the recording, Trim Video first.
Privacy
Screen recordings often show emails, dashboards and personal details. With FixDoks the conversion happens in your browser and nothing is uploaded, so those details stay on your device.
What about MKV and other formats?
This page is tuned for WebM, but the same engine reads MKV, AVI, FLV and 3GP too. If the video inside is already H.264, it is copied into the MP4 without re-encoding, which is instant and lossless. For iPhone and QuickTime files, see MOV to MP4.