WebM to MP4

Free online WebM to MP4 conversion, supporting Chrome screen recordings and web video files. Browser-based, no upload, fully private.

Privacy Protection

All processing is done locally in your browser. WebM files are never uploaded to any server, fully protecting your privacy.

High-Speed Conversion

Powered by WebCodecs with hardware acceleration, quickly converts WebM to MP4 with no upload wait.

High Compatibility Output

Outputs standard H.264 MP4, compatible with iPhone, Android, Windows, and major video platforms.

Drag and drop video files here

or

Supports MP4, WebM, MOV, MKV, AVI, and more

Use Cases

  • Convert Chrome screen recordings saved as .webm to MP4 to share with iPhone or Windows colleagues.
  • Convert web-recorded or captured WebM video to MP4 for import into editing software for post-production.
  • Convert WebM files from online meetings to MP4 for upload to video platforms or internal knowledge bases.
  • Convert WebM clips to MP4 and embed in PowerPoint presentations to ensure playback on all devices.

About WebM and MP4

WebM is Google's open-source video format using VP8/VP9 video and Vorbis/Opus audio, mainly for web video and Chrome screen recording. MP4 is the ISO-standard universal video container with excellent compatibility. This tool uses WebCodecs to convert WebM to H.264 MP4 entirely in your browser — files never leave your device.

Frequently Asked Questions

Why convert WebM to MP4?

WebM is Chrome's default format, but many phones, video apps, and platforms have limited WebM support. Converting to MP4 greatly improves compatibility.

Can Chrome screen recordings saved as WebM be converted?

Absolutely. Chrome screen recording saves as .webm by default — just upload and convert to MP4 for easy playback on other devices.

Will converting WebM to MP4 reduce quality?

Quality loss is minimal at high settings. VP8/VP9 to H.264 conversion at high quality is barely noticeable.

Will the file size change after conversion?

WebM VP9 and H.264 MP4 are similar in size; MP4 may be slightly larger. Use a lower quality setting in advanced options for a smaller file.

What is the maximum WebM file size supported?

Supports WebM files up to 2 GB. Chrome recordings are usually under a few hundred MB and process quickly.

Will my files be uploaded to a server?

No. All processing is done locally in your browser. Files never leave your device, fully protecting your privacy.