Transparent WebM: video with an alpha channel for the web
WebM is the browsers' open video format. Encoded in VP9, it can keep transparency while staying small. Its catch: it doesn't play the same way everywhere.
Can a WebM be transparent?
Yes, if it's encoded in VP9 with an alpha channel. A regular WebM without alpha has no transparency; it's the encoding that matters, not the .webm extension.
It's the most common way to put a transparent video on a web page, because it's much lighter than ProRes 4444.
Where does transparent WebM work?
It plays with transparency in Chromium-based browsers (Chrome, Edge) and in Firefox. Safari, on Mac and iPhone, doesn't handle it the same way and usually needs an HEVC video with alpha instead.
Editing apps don't all handle WebM with alpha either: for editing, green or ProRes 4444 is safer. On a website you'll often provide two files; see transparent video on a website.
Does Keyotte export transparent WebM?
No. Keyotte accepts WEBM files as uploads, but only exports an H.264 MP4 on flat green #00B140, with the sound.
To get a transparent WebM, key out the green in your editor, export ProRes 4444, then convert that file to VP9 WebM with alpha using a tool such as FFmpeg.
How do you convert a transparent file to WebM with alpha?
With FFmpeg, you encode to VP9 (libvpx-vp9) while keeping a pixel format with alpha (yuva420p). The source must already contain transparency, for example a ProRes 4444.
Check the result by opening it in Chrome over a colored background: if you see black, the alpha was lost. The usual causes are in transparent video turns black.
Which settings keep a WebM light?
Keep the frame size matched to how big it's displayed, the clip short and the bitrate sensible. A video shown small on a page doesn't need 1080p.
A loop of a few seconds is often enough for an animated character or product. If it must start on its own, it has to be muted: browsers block autoplay with sound.
Transparent WebM or green background: which should you use?
For a website, transparent WebM is the right call. For editing, keep the green: it opens everywhere and keys out in one effect.
To compare all formats at once, see transparent background videos and the alpha channel.
Export price : €1.99
Remove my video backgroundFrequently asked questions
Does transparent WebM work on iPhone?
Safari doesn't play it the way Chrome does. On iPhone, people usually add an HEVC video with alpha alongside the WebM.
Can I post transparent WebM on social media?
No, platforms re-encode video without transparency.
Is transparent WebM heavy?
It's much lighter than ProRes 4444, which is what makes it suitable for the web.
Does CapCut read transparent WebM?
It depends on the version. For CapCut, the safest bet is a green screen clip with chroma key.