What is a WebM file?
WebM — royalty-free web video
Use the format WEBM
A concrete example
Prepare an MP4 copy of a video animation for editing software.
Useful checks
Check the output codecs and any transparency: it is not preserved in all conversions.
Choose a conversion
Keep the original and open the result in the software or on the device that will need to use it.
Your questions about this format
How to choose between MP4, WEBM, and MKV?
MP4 is suitable for many sharing purposes; WEBM is particularly intended for web playback. MKV may be better suited for content with multiple tracks. Look at the outputs offered for your file and test the result on the player you will actually use.
Can I extract only the audio from my video?
Yes, if MP3 is listed among the outputs of your source. Add the video, choose MP3, and start the conversion. The file must contain an audio track: a silent video cannot produce a sound recording.
Why am I being offered MKV for tracks and subtitles?
Not all outputs retain the same tracks. If the engine indicates that a MKV container is required, go back to the output selection and choose MKV instead of forcing a conversion that would remove elements. This output may fall under NoLimit.
How many videos can I convert for free?
The free offer allows one video per day, within the total quota of ten files and the limit of 100 MB per file. A batch of three files does not add three video rights: the video quota remains shared. A valid NoLimit access adjusts the limits according to the displayed offer.
What is it?
WebM is a video format designed exclusively for the web: lightweight, royalty-free, and playable directly in the browser without an external player.
It's a stripped-down version of the Matroska container, deliberately limited to a handful of open codecs — VP8, VP9 or AV1 for video, Vorbis or Opus for audio.
History & origin
Google released WebM in 2010, after acquiring the company behind the VP8 codec, and made it entirely free of licensing fees.
The goal was clear: give the web an alternative to H.264, which was then covered by a patent pool demanding licensing payments. This effort directly paved the way, a few years later, to AV1.
Why it is useful
Very light files at equal quality, native playback in every browser, and no royalties to pay.
It supports video transparency, which MP4 doesn't — useful for overlaying an animation on a page.
Limits & drawbacks
Outside the browser, compatibility falls apart: TVs, set-top players and editing software often don't support it.
Encoding in VP9 or AV1 is much slower than in H.264.
Practical tips
WebM is the right choice for video embedded in a web page. For emailing a file or playing it on a TV, convert it to MP4 first.
On a website, serving both formats — WebM for modern browsers, MP4 as a fallback — remains the safest strategy.
Convert your WebM in seconds, on our secure servers in France.
Convert a WebM