Dead Pixel Test
Find dead & stuck pixels
The test fills your whole screen with one colour at a time. Look closely across the screen for dots that don't match:
- Dead pixel: a black dot that stays black on every colour.
- Stuck pixel: a dot that stays red, green, blue or white whatever the colour.
- Backlight bleed: bright patches along the edges on the black screen.
Click, tap or press → / Space for the next colour, ← to go back, Esc to finish. Clean the screen first: dust looks a lot like a dead pixel.
Try to fix a stuck pixel
Warning: this flashes colours quickly. Don't use it if you have photosensitive epilepsy or are sensitive to flashing light.
A stuck pixel can sometimes be freed by flashing it rapidly for 10–20 minutes. Drag the flashing square over the stuck pixel and leave it running. Dead (black) pixels can't be fixed this way.
About the Dead Pixel Test
Just bought a monitor, laptop or phone? Check it before the return window closes. The test fills the screen with black, white, red, green, blue and more, one at a time, so a dead pixel (always black) or stuck pixel (always one colour) stands out. The black screen also shows backlight bleed. If you find a stuck pixel, the fixer flashes colours over it, which sometimes brings it back.
- Clean the screen so dust isn't mistaken for a pixel.
- Press Start full-screen test.
- Click, tap or press → to step through the colours, looking closely across the screen.
- Press Esc when you're done.
Frequently asked
What's the difference between a dead and a stuck pixel?
A dead pixel gets no power and stays black on every colour. A stuck pixel is stuck on one colour (often red, green, blue or white). Stuck pixels can sometimes be fixed; dead pixels usually can't.
Can a stuck pixel be fixed?
Sometimes. Running the flashing fixer over it for 10–20 minutes, or gently massaging the spot through a soft cloth while the screen is off, can free it. If not, check your warranty's dead pixel policy.
Does this work on phones and TVs?
Yes. Open the page in the device's browser. On a TV, use a browser app or cast the browser tab.
Is what I type sent to a server?
No. The tool runs entirely in your browser and there's no server behind it, so what you type never leaves your device and nothing is stored. You can check: it keeps working if you go offline after the page has loaded.
More from the Web & QR drawer
Other tools kept in this drawer, plus a few favourites from the bench.