Dead Pixel Test
Check your monitor, phone or TV for dead and stuck pixels, one color at a time.
Quick answer: Press Full screen and step through the colors. A dead pixel is a dot that stays black, and a stuck pixel is a dot that stays one color on every screen.
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 first.
- Press Full screen. Start with white, then black, red, green and blue.
- Look closely at each color for dots that do not match. Press Esc when you are done.
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.
Order of the colors
| Color | Shows up |
|---|---|
| White | Dead pixels (black dots) |
| Black | Stuck and hot pixels (colored or white dots), backlight bleed |
| Red, green, blue | Pixels whose single color has failed |
| Gray | Uneven brightness and banding |
What people use it for
- Buying a monitor or laptop
- Checking a used phone
- Warranty claims
- Checking a TV
Questions
What does a dead pixel look like?
A tiny black dot that stays black on a white screen.
How many dead pixels are acceptable?
It depends on the maker and the screen class. Many warranties allow a few, so check the policy for your model.
Will this test damage my screen?
No. It only shows solid colors.
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.