Convert MP4 to WebM.
Turn MP4 into WebM — the open, web-native video format that's often smaller at the same quality and made for HTML5 <video>. Converted with a local engine, private, and auto-deleted after 1 hour.
Why WebM for the web
WebM is an open, royalty-free container built around the VP9 video and Opus audio codecs, designed specifically for the web. At the same visual quality it's frequently smaller than an H.264 MP4, which means faster page loads and less bandwidth — a real win for hero clips, background loops and anything you embed directly with an HTML5 <video> tag.
Offer both for full coverage
Browser support for WebM is excellent today, but MP4 remains the universal fallback (older Safari, some embedded players). The robust pattern is to ship both and let the browser pick:
<video controls>
<source src="clip.webm" type="video/webm">
<source src="clip.mp4" type="video/mp4">
</video>The trade-off
VP9 compresses harder than H.264, so encoding takes more CPU time — you're spending a bit longer converting in exchange for a smaller, web-tuned file. Need to go back the other way for a universal copy? Use WebM to MP4.
How it works
- 01
Upload your MP4
Drop a file or pick one from your device. Private by default.
- 02
Convert with a local engine
MP4 is re-encoded to WebM (VP9/Opus) with ffmpeg — no paid API in the loop.
- 03
Download
Grab your WebM, ready to embed on the web.
Open, royalty-free format built for HTML5 <video>
Often smaller than MP4 at the same visual quality
Great for background video and fast-loading pages
Private uploads, auto-deleted after 1 hour
No watermark, no signup to try
MP4 to WEBM: transcode
MP4 and WEBM are container/codec formats, so this re-encodes the video (a lossy step — start from the best source you have). WEBM is broadly compatible, which helps when a player, editor or site won't accept MP4.
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Common questions
Is it free?+
Yes — convert MP4 to WebM free. Paid plans add larger files, batch and priority.
Is my file private?+
Your file is uploaded to a private bucket, converted, and auto-deleted after 1 hour — never sent to a third-party converter.
Should I use WebM or MP4 on my site?+
For the widest reach, offer both — modern browsers prefer WebM (smaller), and MP4 (H.264) is the universal fallback. In an HTML5 <video> tag, list the WebM <source> first and an MP4 <source> after it.
Why does it take a bit longer?+
WebM's VP9 codec compresses harder than H.264, so encoding is more CPU-intensive — you trade a little conversion time for a smaller, web-optimized file.
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