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WebM to MP4 converter online free

Convert WebM to MP4 online free in your browser. Turn .webm videos into H.264 MP4 with adjustable quality — no server upload required.

What is a WebM to MP4 converter?

A WebM to MP4 converter changes WebM videos into the widely supported MP4 format, usually with H.264 video and AAC audio. People search webm to mp4, webm converter, or convert webm file to mp4 when a site, editor, or phone needs MP4 instead of WebM. This tool runs locally in your browser with FFmpeg WebAssembly — no server upload.

WebM to MP4 converter features

Browser-based WebM to MP4 conversion with privacy-first processing.

  • Convert WebM to MP4 online

    Upload a .webm file and download a compatible MP4 in your browser.

  • WebM converter for any clip

    Works with screen recordings, browser exports, and downloaded WebM videos.

  • Adjustable output quality

    Tune H.264 CRF to balance visual quality and MP4 file size.

  • No server upload

    FFmpeg WebAssembly processes video on your device for better privacy.

  • Web-ready MP4

    Output uses H.264, AAC, and faststart for broad playback compatibility.

How to convert WebM to MP4 online

Convert a WebM file to MP4 in three steps.

  1. Upload WebM file

    Drop or select your .webm video (up to 200 MB).

  2. Set quality (CRF)

    Keep the default CRF 23 for balanced quality, or lower CRF for sharper output.

  3. Convert and download

    Click Convert to MP4, then download the result.

Great for

Common WebM to MP4 conversion scenarios.

  • Editors and apps that need MP4

    Turn WebM exports into MP4 for Premiere, DaVinci, or mobile editors.

  • Social and web uploads

    Convert WebM before posting to platforms that prefer MP4.

  • iPhone and Apple workflows

    MP4 plays more easily than WebM in Photos and many Apple apps.

  • Sharing by email or chat

    Create MP4 files recipients can open without a WebM-capable player.

Frequently Asked Questions

Quick answers about this tool—open a question to read more.