Practical guide
Dead Pixel Test: How to Check a Monitor or Phone Screen
Use full-screen solid colors to find stuck, dead, or bright pixels and avoid confusing dust, reflections, or image retention with a panel defect.
A dead-pixel check works best with a clean screen, controlled light, and several solid colors viewed at normal distance and close range.
Fullscreen Solid colors Keyboard and touch controls
01
Before you start
Close competing apps, connect the device directly when possible, and keep this tab visible while the test runs.
Open the live tool02
Run the check step by step
- Clean the screen gently and start the full-screen color sequence.
- Use click, touch, or arrow keys to inspect every solid color.
- Exit visibly at any time and note whether a mark changes across colors.
03
How to read the result
A spot that stays dark on every color may be a dead pixel; one fixed bright color may be stuck. Clean the screen and repeat before drawing a conclusion.
What the browser cannot prove
- The test does not photograph, detect, repair, or guarantee a diagnosis of physical pixels.
- Dust, coating marks, and stuck pixels can look similar; compare several colors.
04
Common questions
Is the Dead Pixel Test private?
Yes. Test input is processed in this tab and is not uploaded by this tool.
Why can browser results differ from another app?
Browsers, operating systems, permissions, device routing, and background load can all change what is exposed and measured.
Dead Pixel Test
Open the live tool