Red Screen
A solid red page (#FF0000). Press Fullscreen to fill the display and Esc to exit.
What a red screen is useful for
- Pixel testing. Every pixel has red, green and blue parts. On a red screen only the red part is lit, so a pixel whose red part has failed shows as a dark dot, and one stuck on green or blue shows as a different colour. The full method is in the dead pixel test guide.
- A light that is easier on dark-adapted eyes. Dim red light disturbs night vision less than white light, which is why astronomers use red torches. Lower the brightness and use it to read a star chart or find something in a dark room.
- Coloured lighting. A red glow for photos, video, parties or a darkroom look.
- Checking colour uniformity. Patches that look pink or orange point to an uneven panel.
Note that real photographic darkrooms need a proper safelight. A monitor's red is not pure enough to protect photographic paper.
Red screen FAQ
What does a red screen test show?
It shows whether the red part of every pixel works. Dark dots are pixels with a failed red sub-pixel, and dots of another colour are stuck sub-pixels.
Is red light better at night?
Dim red light affects night vision less than white or blue light. Keep the brightness low for the best effect.
Can I pick a different shade of red?
Yes. Use the colour box in the toolbar to choose any shade.
More tools
- White ScreenPure white for light, tracing and pixel checks.
- Black ScreenPure black to go dark, clean or test.
- Green ScreenPure green for chroma key and pixel tests.
- Blue ScreenPure blue for pixel tests and chroma key.
- Hacker TyperThe classic: mash any key, get lines of kernel code.
- Hacker SimulatorA full fake hacking dashboard with one click.
- Fake Update ScreenWindows, Mac and more: an update that never finishes.
- Matrix RainFalling green code with colour, speed and size controls.