Dead Pixel Test
Fill your screen with pure red, green, blue, white and black to spot dead, stuck or hot pixels and backlight bleed on monitors and phones.
Runs on your device
What it does
Dead pixels show as black dots on bright colours; stuck pixels show as a single coloured dot. Go fullscreen and cycle through the colours slowly.
How to use it
- Press Start fullscreen test.
- Click or press the arrow keys to change colour.
- Look closely for dots that do not match.
When it helps
- Checking a new monitor within the return window.
- Buying a used laptop or phone.
- Finding backlight bleed.
Questions
Can a stuck pixel be fixed?
Sometimes. Rapidly flashing colours over the spot for a while can free a stuck subpixel, but dead pixels cannot be repaired.
How do I exit?
Press Escape.
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