WebM to MP4 Converter

Convert WebM video files to MP4 format online. Free, fast, and private.

Upload your WebM videos and convert them to MP4 for universal playback. WebM is a web-focused format used by YouTube, Google Chrome, and Firefox, but many devices and media players do not support it. MP4 plays on everything. All conversion happens in your browser using WebAssembly. Your videos never leave your device. Need a different conversion? Try MOV to MP4 or our video compressor.

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Drop WebM files here

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Supports: WebM video files

How It Works

  1. 1
    Upload WebM files

    Click or drag and drop your .webm video files. These are commonly downloaded from YouTube or recorded in Chrome/Firefox.

  2. 2
    Choose quality settings

    Select output quality and resolution. High quality with original resolution keeps your video looking the same.

  3. 3
    Convert and download

    Click Convert to MP4 and download your files. Preview the converted video before saving. Need to cut it down? Use the Video Trimmer.

Frequently Asked Questions

Why convert WebM to MP4?

WebM is an open format developed by Google that works well in web browsers. However, many devices, media players, and video editing software do not support WebM. MP4 is the universal video standard that works on all phones, TVs, computers, and social media platforms.

Where do WebM files come from?

WebM files are commonly produced by YouTube downloads, screen recordings in Chrome or Firefox, Google services, and web-based video tools. If you have a .webm file that won't play on your phone or TV, converting to MP4 will fix that.

Will the file size change?

The file size depends on the quality setting. At High quality, MP4 files are typically similar in size to the original WebM. WebM (VP9) and MP4 (H.264) are both efficient modern codecs. Lower quality settings will produce smaller MP4 files. Check our MP4 vs WebM comparison.

Are my videos uploaded to a server?

No. All conversion runs in your browser using FFmpeg WebAssembly. Your videos never leave your device. No data is uploaded, stored, or tracked. See our security page.

Can I convert WebM audio-only files?

This tool is designed for video WebM files. If you have audio-only WebM/Opus files, you can still convert them but the output will be an MP4 container with just the audio track. For audio conversion, try our audio compressor.

Is this converter free?

Yes. This WebM to MP4 converter is completely free with no file limits, no signup, and no watermarks. Convert as many videos as you need. You can also convert videos to GIF or extract audio from your videos.

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