Cycle through full-screen solid colours and gradients to spot screen defects.
What is the Dead Pixel Test?
A dead pixel stays black, and a stuck pixel stays one colour (red, green or blue). They are easiest to spot on a full-screen solid colour. This test fills your screen with black, white, red, green, blue, yellow, cyan, magenta, grey and gradients so you can check a new or second-hand monitor, laptop, TV or phone screen.
Black screens also reveal backlight bleed (light leaking from edges) and white/grey screens show uneven brightness.
How to use the Dead Pixel Test
- Clean your screen and set brightness high.
- Start the full-screen test.
- Click or press → to change colours; look closely for dots that do not change.
Found a stuck pixel?
Stuck pixels can sometimes be fixed by gently massaging the area with a soft cloth or running a rapidly flashing colour video for a while. Dead pixels usually cannot be fixed – check the manufacturer’s pixel warranty policy.
Frequently asked questions
How many dead pixels are acceptable?
It depends on the manufacturer’s policy (ISO 9241-307 classes); many allow a few.
Does it work on phones?
Yes, tap to change colours.
Can a dead pixel spread?
Normally no.
Is it free?
Yes.
This dead pixel test is 100% free, needs no signup and works on phones, tablets and computers.
Last updated: · By NodifyTech