Convert WebM files to MP4 online - no software, no uploads, no waiting. Hardware-accelerated conversion runs entirely in your browser.
Perfect for screen recordings, browser captures, and more
WebM is an open video format developed by Google, commonly used for web videos and screen recordings. While WebM works great in Chrome and Firefox, you'll run into problems when you try to:
MP4, on the other hand, is the universal video format. It plays on every device, works with every app, and uploads anywhere. When you convert WebM to MP4, you're trading a web-only format for one that works everywhere.
Unlike cloud-based converters that upload your video to a server, Kommodo's converter runs entirely in your browser. Your WebM file never leaves your device. We use WebCodecs API for hardware-accelerated encoding, which means:
Just drop your WebM file, wait a few seconds, and download your MP4. It's that simple.
Your videos stay on your device. No uploads, no cloud processing, complete privacy.
Hardware-accelerated encoding via WebCodecs makes conversion incredibly fast.
MP4 works everywhere - iPhones, Android, Windows, Mac, social media, and more.
Smart re-encoding preserves your video quality during conversion.
Click to browse or drag and drop your WebM video file.
Conversion starts immediately with hardware acceleration.
Click Download to save your converted video.
Convert WebM to MP4 for universal compatibility
Drop your WebM file into the converter above. Conversion starts automatically and takes just seconds. Click Download to save your MP4 file. No account, no uploads to servers, completely free.
Yes. This converter runs entirely in your browser using WebCodecs technology. No downloads, no installations, no plugins required. Works on Windows, Mac, Linux, and Chromebook.
Completely free with no hidden costs. No watermarks on your video, no file size limits, no time restrictions, and no account required. Convert as many files as you need.
iOS does not support WebM format natively. Converting your WebM to MP4 will make it playable on any iPhone, iPad, or Apple device. MP4 is universally supported across all platforms.
Our converter uses high-quality encoding settings to preserve video quality. For most videos, the difference is imperceptible. We prioritize quality over file size reduction.
No. All conversion happens directly in your browser. Your video file never leaves your device, ensuring complete privacy. This is different from cloud-based converters that require uploads.
Chrome, Edge, and Chromium-based browsers offer the fastest conversion using hardware acceleration. Firefox and Safari work too, but use software encoding which is slower.
Yes, if you're using Chrome on Android. The converter works in mobile browsers, though conversion may be slower than on desktop. For iPhone users, you'll need to use a desktop browser since Safari has limited WebCodecs support.
With hardware acceleration enabled, most videos convert in seconds. A 5-minute video typically converts in under 30 seconds. Longer videos or devices without GPU support will take longer.
There's no file size limit. Since conversion happens locally on your device, you're only limited by your browser's available memory. We've tested files up to 2GB successfully.
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