How to Check a Used Phone Screen
Use a fast visual checklist to inspect a used phone screen before buying or selling it.
Quick answer
Before buying a used phone, inspect solid colors for dead or stuck pixels, low gray for OLED wear, and a drawing test for touch dead zones. Repeat suspicious results after cleaning the glass and removing screen-protector glare.
Last reviewed: July 30, 2026 · Testing method and editorial policy
Check image quality first
Look for fixed dark or colored dots, vertical lines, tint, bright pressure marks and uneven brightness. On OLED phones, low gray can reveal faint keyboard, status-bar or navigation shadows.
Test the whole touch surface
Draw slow horizontal and vertical lines over the center, edges, corners and keyboard area. Clear the canvas and repeat any gap in the same place before calling it a dead zone.
Separate browser limits from hardware
Multi-touch counts can be limited by the browser, operating system or device. Use repeatable missed touches and fixed visual marks as evidence, not a single browser reading.
How to verify it
- Clean the glass and use a comfortable brightness.
- Check white, black, primary colors and low gray.
- Draw across the full touch surface and repeat any gaps.
- Record fixed defects before paying or accepting a repair.