How to Test Touch Screen Dead Spots
Check whether a phone, tablet or laptop touchscreen has unresponsive areas and document repeatable dead spots.
Quick answer
Test touch-screen dead spots by drawing slow horizontal, vertical and diagonal lines across the entire display. A gap that repeats in the same physical area after cleaning and retesting may indicate an unresponsive digitizer zone.
Last reviewed: August 1, 2026 · Testing method and editorial policy
Remove common interference
Dry the glass and your hands, disconnect a noisy charger, and compare with and without a removable protector or case when practical.
Repeat the exact path
One missed stroke is not enough. A hardware dead zone usually interrupts lines repeatedly in the same location, including edges, corners and keyboard areas.
Check multi-touch separately
If the problem happens only while zooming, gaming or typing, compare the multi-touch test because simultaneous-touch limits can differ from single-touch behavior.
How to verify it
- Clean and dry the screen, then open the drawing surface.
- Draw a slow grid from edge to edge.
- Clear the canvas and repeat every suspicious gap.
- Run multi-touch testing and document repeatable failures before repair or purchase.