Dead Pixel Test
Fill your whole screen with solid colors and look for pixels that stay dark, bright or colored.
Start the test, then click or press Space / → for the next color, ← to go back and Esc to exit.
How to find dead pixels
- Clean the screen first — dust looks like a dead pixel.
- Raise brightness to maximum, start the test and step through every color.
- On white, a dead pixel shows as a black dot. On black, a stuck pixel shows as a bright dot.
- On red, green and blue, a sub-pixel that is stuck off or on shows as a dot of the wrong color.
Dead, stuck and hot pixels
Dead pixel: always black, never lights. Stuck pixel: always one color (red, green, blue). Hot pixel: always white. Stuck pixels can sometimes be revived by gently massaging the spot or running a flashing-color tool; dead pixels usually cannot.
FAQ
Does this work on phones, laptops and TVs?
Yes. Open this page in any browser on the device and use the full-screen mode. On a TV, use its built-in browser or cast the page.
How many dead pixels are acceptable?
It depends on the manufacturer’s policy (often described by an ISO 9241-307 class). Check your warranty terms before returning a display.
What is backlight bleed?
Light leaking at the edges, visible on the black screen in a dark room. It is a panel quality issue, not a dead pixel.