About this test
Each colour reveals a different defect: a dead pixel shows as a black dot on white, a stuck pixel stays lit in red, green or blue on every background, and a black screen in a dark room shows backlight bleed and IPS glow. Patterns help check sharpness and scaling. Use it before the return window ends on a new screen.
How to use this test
- Clean the screen, then press Start full-screen test.
- Click or press → to cycle through each colour and pattern.
- Look closely at every area. Note the position of any dot that does not match the colour.
Frequently asked questions
What is the difference between a dead and a stuck pixel?
A dead pixel never lights up and appears black. A stuck pixel is always on in one colour. Stuck pixels can often be fixed with the Pixel Healer.
How many dead pixels are acceptable?
It depends on the manufacturer's pixel policy. Many allow a few, while premium lines offer zero bright-pixel guarantees.