How to Check Dead Pixels on a Phone
A phone-friendly workflow for checking dead pixels, stuck pixels and screen protector marks on iPhone, Android and used phones.
Quick answer
To check a phone for dead pixels, clean the glass and inspect fullscreen white, black, red, green and blue screens. A dead pixel usually stays dark in the same physical spot; a stuck or hot pixel stays bright or colored.
Remove phone-specific false positives
Check for dust under a screen protector, privacy-filter darkening, scratches, camera cutouts and interface icons. These can resemble pixel defects but may change with angle, cleaning or content.
Add touch and OLED checks
For a used or repaired phone, draw lines across the full touch screen to find dead zones. On OLED phones, also use low gray to look for fixed keyboard, status-bar or navigation shadows.
Document a repeatable problem
Do not press hard on the suspected spot. Repeat the color sequence, note the brightness level and take a clear photo only after the mark remains fixed across several backgrounds.
How to verify it
- Remove obvious dirt and set brightness to a comfortable level.
- Inspect the screen edge to edge on white, black, red, green and blue.
- Repeat the check without a removable screen protector if it may contain dust.
- Run a touch test and low-gray OLED check before buying a used phone.