Red Screen.
Open a red screen in full screen, explore shades, or download a solid red background.
Choose your color
Click to previewScreen settings Dimming & keep awake
This changes the displayed color. Adjust your device brightness for a brighter or dimmer screen.
Works only while this page is visible. Your system may still interrupt it.
Download a plain background
#FFFFFFA clean, solid image. No border, watermark or dimming.
Key takeaways
- #FF0000 lights only the red subpixels, at full strength.
- Red gives about 21 % of the brightness of white.
- A dark point on red can mean a red subpixel that does not light.
Pick a color
Start with red, choose a preset or enter your own HEX code.
Make it full screen
Open the color across your screen. Press Escape or tap Exit to return.
Take it with you
Download a plain PNG or JPG in the size that fits your project.
A clear view of pure red.
Red uses RGB 255, 0, 0. Display it to inspect one primary color, or download a bold, plain red background for a layout or presentation. For a sequence of test colors, use the manual pixel test.
Why test a screen with pure red?
Because pure red uses one of the three subpixels in each pixel and leaves the other two off. If a red subpixel never lights, that pixel shows as a dark point on red. If a green or blue subpixel is stuck on, it adds its colour and the point looks yellowish or pinkish instead of red.
| You see on red | Possible reason |
|---|---|
| Dark point | Red subpixel not lighting |
| Yellow-looking point | Green subpixel stuck on |
| Pink or purple-looking point | Blue subpixel stuck on |
Compare the same spot on the other test colours before deciding; dust can look the same.
Find your color.
Questions, answered.
Why does red look darker than white at the same brightness?
Red adds up to about 21 % of the luminance of white in the standard sRGB weighting, because our eyes are most sensitive to green.
Can red fix a stuck pixel?
No. This is a static color surface. It neither detects nor repairs pixels, and has no flashing repair mode.
How do I leave full screen?
Press Escape or move your mouse or touch the screen to reveal Exit. Press F to toggle full screen when you are not typing in a field.
Does it work on phones and tablets?
Yes. If your browser cannot open true full screen, the color fills the browser window instead. Browser bars may remain visible. You can use portrait or landscape orientation.
Can this change my device brightness?
No. Screen dimming darkens the displayed color only. Use your device’s brightness controls to adjust the physical display.
What does Keep screen awake do?
When supported and allowed, it asks your browser to keep the display on while this page is visible. The status shows whether the request is active, released or unavailable. Battery settings and system behavior may override it.
Can I download a 4K background?
Yes. Choose 4K UHD for a 3840 × 2160 image. Images are created on your device and contain the selected base color only, without the dimming effect.
Sources: W3C, CSS Color Module Level 4, named colors; W3C, WCAG 2 definition of relative luminance. Last reviewed November 12, 2026.