What a green screen is used for
- Chroma key backgrounds for video calls and streaming, at small scale
- Testing that every green subpixel works
- Filling a monitor behind a subject as a cheap key surface
- Checking green channel uniformity across a large panel
Green screen online: #00FF00 at full screen
Green is the chroma key colour because human skin contains very little of it, and because digital sensors capture roughly twice as much green data as red or blue — most camera sensors use two green photosites for every red and blue one. That extra resolution makes a green key cleaner to cut than a blue one.
This page defaults to #00FF00, pure digital green, which is what most people mean by “green screen” and what the other sites serve. Professional chroma key fabric and paint is a slightly duller #00B140 — it reflects less light onto your subject and spills less green onto their hair and shoulders. Both are in the palette; if you are actually keying, try the duller one first.
A monitor makes a poor key surface at any real size, because it is a light source rather than a lit surface, and it will spill green onto anything close to it. For a head-and-shoulders shot on a call it is fine. For anything larger, fabric lit separately will always beat a screen.
How to get a full screen green background
Press the fullscreen button on the player above, or the F key. Escape returns you to the page. On a desktop browser F11 does the same job and hides the browser's own toolbars as well.
The colour box is a control, not a picture: use the hex field to enter any value, pick another shade from the palette, or download the current colour as a PNG at your screen's resolution. Whatever you set is written into the address bar, so the link you copy reproduces exactly what you are looking at.