Red screen
Fill your entire screen with pure red — to expose stuck or dead red subpixels, or as gentle red light that preserves night vision. Click or press Esc to exit.
More color screens
Red screen FAQ
- What is a full red screen used for?
- Mainly for pixel checks: a pure red field drives only the red subpixel of every pixel, so a stuck or dead red subpixel stands out immediately as a dark or off-color dot. It's also popular as ambient red light — photographers and stargazers use a dim red screen because red light disturbs dark-adapted eyes far less than white.
- I found a dot that stays dark on red — what is it?
- A dark dot only on red means that pixel's red subpixel isn't firing — a dead subpixel. A dot that's the wrong color (say, always lit bright) is stuck rather than dead. Run the full dead pixel test to check the other channels: cycling red, green, blue, white, and black tells you exactly which subpixel is at fault and whether it's stuck or dead.
- Can stuck pixels be fixed?
- Sometimes. Stuck pixels (lit in one color) occasionally recover from rapid color cycling or a gentle massage through a soft cloth, though evidence is anecdotal. Dead pixels (always black) almost never come back. If the panel is new, count the defects — most manufacturers replace panels above a documented threshold, so check the warranty policy before trying anything physical.