What a magenta screen is used for
- Confirming the green channel is fully off — any green dot is a fault
- Checking red and blue subpixels together
- Bold lighting for photography and stage-style looks
- Print work needing a screen reference for magenta
Magenta screen online: #FF00FF at full screen
Magenta is the complement of green: red and blue at maximum, green at zero. A stuck green subpixel is glaringly obvious on this field, which is why magenta belongs in any subpixel test sequence alongside cyan and yellow.
Magenta is also a genuine oddity in colour science. It does not exist as a wavelength — there is no magenta light in a rainbow. It is what the brain invents when the red and blue cones fire together and green does not, which is to say it is a colour that exists only in perception.
In printing it is one of the three subtractive primaries. Screen magenta is considerably more vivid than printed magenta, for the same gamut reasons as cyan.
How to get a full screen magenta 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.