Primary tool

Touch Screen Tester

Draw with fingers, check dead zones, and detect ghost touches — all in one place.

Free Open Source Touch Screen Test

Draw with your fingers to test for dead zones. Works on phone, tablet and touch laptops.

0 Active Fingers

0 Max Simultaneous

0 Total Touches

This test runs entirely in your browser. No data is collected.

For best results, open this page on your phone or tablet.

Tests dead zones

Draw across the entire surface to expose unresponsive areas

Ghost touch detection

10-second idle test flags phantom inputs automatically

Multi-touch support

Counts simultaneous finger contacts in real time

Works on any device

Phone, tablet, or touch laptop — no app needed

How to Test Your Touch Screen

Draw with your finger across the entire screen surface. Any area where no trail appears is a dead zone. Cover all four corners and edges as these areas most commonly develop dead zones after screen damage. A uniform colour trail from corner to corner means the digitizer is responding correctly across the full display area.

Cover the corners first

Corners take the most physical stress. Swipe diagonally through each corner to confirm all four edges respond.

Slow and steady strokes

Draw slowly so you can see exactly where the trail stops or skips, rather than fast swipes that are hard to read.

Remove screen protectors

A poorly adhered or thick screen protector can create air-gap dead zones. Test with and without it to compare.

Repeat after cleaning

Moisture or grime on the glass can create false negatives. Dry the screen thoroughly and retest before drawing conclusions.

What Are Ghost Touches?

Ghost touches are inputs your screen registers without you touching it. Common causes include a damaged digitizer, water damage, a faulty screen protector, or electromagnetic interference from a nearby charger or cable. Use the Ghost Touch Test above to check for 10 seconds without touching the screen. If touches appear on the canvas while your hands are clear of the display, the digitizer is generating phantom input.

Cracked digitizer

A damaged digitizer layer often sends continuous phantom signals in the cracked region, even when the LCD panel looks intact.

Water or humidity damage

Liquid bridging internal circuits can cause erratic phantom taps. Allow the device to dry completely and retest.

Charger interference

Cheap third-party chargers generate electrical noise that travels through the ground path and interferes with the capacitive layer.

Faulty screen protector

Tempered glass protectors with trapped air bubbles or conductive adhesive can disrupt the capacitive field and create ghost events.

Multi-Touch Test

Place multiple fingers simultaneously on the screen. Most smartphones support 5–10 touch points. Tablets typically support 10 or more. The Max Simultaneous counter above shows the highest number of contacts recognised at once. If your device only registers 2 fingers, apps requiring pinch-to-zoom or multi-finger gestures may not work correctly.

What most devices support

Modern Android and iOS phones typically support 5 to 10 simultaneous touch points. Budget devices often stop at 5.

Why it matters for apps

Piano and instrument apps, drawing apps, and multi-player touch games all require 4 or more simultaneous inputs to work as intended.

Pinch-to-zoom minimum

Pinch gestures require at least 2 registered contacts. If your device misses one, zoom and rotate gestures will feel broken or reversed.

Touch laptop note

Windows touch laptops and convertibles typically support 10 touch points but can vary by manufacturer and driver version.

Should I Repair or Replace a Faulty Touch Screen?

If dead zones cover less than 10% of the screen and are in a non-critical area, repair is usually worth it. If ghost touches are frequent and affect usability — triggering random taps, scrolls, or app launches — screen replacement is recommended. Always test a repaired screen with this tool before leaving the repair shop to confirm all areas respond and no ghost touches remain.

Before authorising repair

Use this tool to document the exact location of dead zones so you can verify the same area is fixed after the repair.

After repair verification

Run the full-surface draw test, multi-touch test, and 10-second ghost test in the shop before you hand over payment.

Digitizer vs full assembly

Some repair shops only replace the glass layer, not the digitizer beneath. Confirm the digitizer is also replaced if ghost touches persist post-repair.

Related: Dead Pixel Test

A faulty screen replacement can also introduce dead pixels. After any screen repair, also run our Dead Pixel Test to check the LCD panel.

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