Dead Pixel Test
Check a screen for dead or stuck pixels.
Clean the screen, set brightness to maximum, then start. Each colour fills the whole screen; look closely for tiny dots that don't match.
How to use
- 1Clean the screen and turn brightness up.
- 2Click Start full-screen test.
- 3Tap or press → to go through each colour.
- 4Look for tiny dots of the wrong colour, then press Esc to exit.
Frequently asked questions
What is the difference between dead and stuck pixels?
A dead pixel stays black on every colour (easy to see on white). A stuck pixel stays one colour, like red or green, and shows up on black.
When should I run this test?
Right after buying a phone, laptop or monitor, while you can still return or replace it.
Can a stuck pixel be fixed?
Sometimes. Gently massaging the spot or running a fast flashing-colour video for a while can revive a stuck pixel; dead pixels usually can't be fixed.
What does the grey screen show?
Uneven brightness and backlight bleed, which appear as lighter patches near the edges.
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