Touch Screen Test
Find dead zones, ghost touches and multi-touch limits on any phone, tablet or touch monitor.
Drag a finger, stylus or mouse across this area. Every square you touch turns green — squares that stay dark are dead zones.
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This touch screen test runs 100% locally in your browser. Touch coordinates and device details never leave your device.
No pointer is down. If circles appear here while nothing touches the screen, your panel is producing ghost touches.
How to Test a Touch Screen for Dead Zones
Open the test surface
Open the Touch Screen Test on the device you want to check. Tap "Fullscreen" on a phone or tablet so the test covers the entire display.
Sweep every part of the screen
Drag one finger slowly over the whole grid. Each square turns green the moment it registers your touch, so any square that stays grey is an unresponsive dead zone.
Read the results
Check the coverage percentage, then place several fingers down at once to confirm the maximum number of simultaneous touch points your digitizer reports.
What This Touch Screen Test Checks
A touch screen is made of a display panel plus a separate touch (digitizer) layer that senses your finger. When that layer is cracked, water damaged or partly disconnected, the display can still look perfect while parts of it stop responding — the classic "dead zone". Because the failure is invisible, the only reliable way to find it is to touch every square of the screen and see which regions never report input.
This test turns your screen into a grid and marks each square the instant a touch, pen or mouse pointer passes over it, while drawing the raw pointer trail underneath. That gives you two independent signals: the coverage grid shows which regions are dead, and the trail shows whether tracking is jumpy, offset or breaks up mid-swipe. The pressure and contact-size readouts (reported by pens and some touch panels) help you confirm a stylus is being sensed correctly.
The multi-touch counter is useful in a different way: it reports the maximum number of simultaneous contact points the browser observed. If a device that should support 10-point multi-touch only ever reports 2 or 3, the digitizer or the driver is limiting input, which shows up in games and gestures like pinch-to-zoom.
Frequently Asked Questions
How do I test if my touch screen has dead zones?+
Open this touch screen test in fullscreen and drag one finger slowly across every part of the display. Each grid square turns green when it detects your touch. Any square that stays grey after you have covered it is a dead zone — an area where the digitizer no longer registers input.
How many touch points does my phone or tablet support?+
Place as many fingers on the test surface as you can at the same time. The "Max simultaneous" counter records the highest number of touch points the browser reported. Most modern phones support 5 to 10 points; many budget or damaged panels top out lower.
What is a ghost touch and can this tool detect it?+
A ghost touch is input your screen reports when nothing is touching it — often caused by a damaged digitizer, a bad screen protector or a faulty charger. Leave the test surface untouched and watch the active-pointer counter: if circles appear or the counter rises on its own, your screen is registering ghost touches.
Does this touch screen test work on a laptop or touch monitor?+
Yes. The test uses the browser Pointer Events API, so it works with touch screens, styluses, trackpads and mice on any device. The "Input types" readout tells you whether the browser saw touch, pen or mouse input.
Is my touch data sent anywhere?+
No. Everything runs locally in your browser using JavaScript. No touch coordinates, drawings or device details are uploaded, stored or shared, and no app or install is required.
My screen has a dead zone — what should I do?+
First remove any case or screen protector, clean the display and restart the device, then re-run the test. If the same area still fails, the digitizer layer is likely damaged and the panel needs repair or replacement. Recording the exact failing region from this test helps a repair shop confirm the fault.