Find dead or stuck pixels and backlight bleed with full-screen solid colours and test patterns. Great for checking new monitors, phones and TVs. Free.

Use the colour buttons or arrow keys to cycle through full-screen test colours. Look closely for dots that stay black (dead) or stuck on one colour.

Colours
How to read the test
  • Dead pixel — stays black on every colour.
  • Stuck pixel — stays one fixed colour (often red, green or blue).
  • Backlight bleed — uneven brightness, most visible on the black screen.
Click / tap or press Esc to exit · ← → to change colour

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