Convert MP4 to WebM Online
To convert an MP4 to WebM, upload your video below, choose WebM as the output format, and download the web-optimized file — no command line and no desktop encoder needed.
WebM was designed for the web: it typically produces smaller files than a comparable MP4 and plays natively in Chrome, Firefox, and Edge through the HTML5 video tag. That makes it a favorite for background videos, product demos, and page embeds where every megabyte affects load time and Core Web Vitals.
How it works
- 1
Upload your MP4
Add the source video — exports from your editor, phone clips, anything up to 500 MB. Upload runs straight from the browser.
- 2
Select WebM output
Pick WebM in the format dropdown. The same tool converts to MP4, MOV, AVI, and MKV, so you can produce multiple versions if your site serves fallbacks.
- 3
Download and embed
Grab the WebM and drop it into your video element or bundler assets. Keep the original MP4 as a fallback source for Safari users.
Why use Video-Matic
Lighter pages
WebM compression is efficient, so hero videos and demo loops usually weigh less than their MP4 counterparts — visitors see content sooner.
Built for HTML5
Chrome, Firefox, and Edge decode WebM natively, making it a first-class citizen in modern video elements and open-source players.
One tool, five formats
Need a fallback MP4 or an MKV archive of the same clip? The converter outputs all five major containers from one upload flow.
Free to try
Three credits come free with signup and each conversion costs one, so you can test WebM on your site before spending anything.
Frequently asked questions
Is WebM smaller than MP4?›
In most cases, yes — the codecs used in WebM compress more efficiently at the same visual quality, so a converted file is often noticeably lighter than the source MP4. Exact savings depend on the footage. For web embeds, smaller files mean faster first paint and less mobile data burned by autoplaying video.
Do all browsers play WebM?›
Chrome, Firefox, Edge, and Android browsers play WebM natively. Safari support has historically been partial, so the standard practice is to list a WebM source first and an MP4 source second inside your video element — browsers pick the first format they can decode. You can generate both versions with this converter.
What does converting MP4 to WebM cost?›
One credit per conversion. A free account includes 3 credits, so your first three files convert for free with no watermark added. Additional credits are sold in one-time packs on the pricing page — no subscription, pay only when you need more.
How long are my files kept on your servers?›
Uploads and converted outputs are deleted automatically within 24 hours, and everything is processed on EU servers in Paris. Download your WebM promptly after conversion; if you miss the window, just upload the source again — the conversion only takes a minute.