Screen Test
Fill your screen with solid colors to check for dead pixels, stuck pixels and uneven backlight.
Quick answer: Press Full screen, then tap or press Space to step through white, black, red, green, blue, gray, cyan, magenta and yellow. Look for dots that do not change or patches that look uneven.
Press F for full screen, Esc to leave. In a series, tap, press Space or use the arrow keys for the next colour.
Very bright full screens can be uncomfortable in a dark room. Do not look at them for long, and do not use them as a warning light on the road or a safety lamp.
How to use it
- Clean the screen with a soft dry cloth first, because dust looks like a dead pixel.
- Press Full screen and look at each colour from about arm's length.
- Tap, press Space or use the arrow keys for the next colour. Press Esc to leave.
What to look for
- Dead pixel: a tiny dot that stays black on every colour. It shows best on the white screen.
- Stuck pixel: a dot that stays one colour, such as red, green or blue. It shows best on a black or white screen.
- Hot pixel: a dot that stays white on a black screen.
- Backlight bleed: pale patches near the edges on a black screen in a dark room. A little is normal on many LCD screens.
- Uneven colour: patches that look yellow, blue or dirty on the white or gray screen.
Good to know
The test shows what your screen does right now, and the result depends on the screen, the brightness and the room. If you find a dot, note its place and colour. Rules for returns and warranty differ by maker and by shop, so check them before you buy or return a screen.
What people use it for
- Checking a new monitor, laptop or phone
- Buying a used screen
- Checking a screen after a repair
- Finding dust or marks on a display
Questions
How do I test my screen for dead pixels?
Show solid white, black, red, green and blue full screens and look for dots that stay a different colour.
What is the difference between a dead and a stuck pixel?
A dead pixel stays black. A stuck pixel stays one colour, such as red or green.
Can a dead pixel be fixed?
A dead pixel usually cannot. A stuck pixel sometimes goes away by itself. Do not press hard on the screen.
Does the test work on a phone?
Yes. Use the full screen button, and rotate the phone if you want to check the whole screen.
Is it free?
Yes. No sign-up, no install and no limit.
Is anything saved or sent?
No. Everything runs in your browser. Only your own best score, where a page shows one, is kept on your device.
Last updated 2026-10-24. Free to use, no sign-up. Made by ficklestudio26.