Drag across every part of this box. Blank patches are dead zones. Use several fingers to test multi-touch.
Coverage
0%
Fingers now
0
Max simultaneous
0
Cells filled
0/352
Hardware TesterFree browser tests for your webcam, mic, keyboard, mouse, controller and display.
Touchscreen test: find dead zones and check multi-touch
This touchscreen test checks that every part of your screen responds to touch and that multi-touch works. Drag your finger across the whole surface to paint it in. Any patch that stays blank is a dead zone that isn't registering. Place several fingers down at once to see how many simultaneous touches your device supports. It runs in the browser on phones, tablets and touch laptops, with nothing to install.
How to test a touchscreen for dead zones
Slowly drag one finger over every part of the test area, right into the corners and edges. Covered cells fill in and a coverage percentage climbs toward 100%. If a region refuses to fill no matter how you swipe it, that area of the digitiser isn't reading your touch, a dead zone. Dead zones often come from a cracked panel, a failing digitiser, or sometimes a screen protector or case pressing on the edges.
Testing multi-touch
Press several fingers onto the screen at the same time. Each touch appears as its own numbered circle, and the test reports the most simultaneous touches it has seen. Modern phones handle 5 or 10 points; if two fingers register but a third doesn't, your device or browser may cap multi-touch, or part of the panel may be faulty. This is worth checking before blaming a game or drawing app for missing inputs.
Touch accuracy and ghost touches
While you drag, the circles should track your fingers smoothly with no jumps. Touches that appear where you aren't pressing (ghost touches) point to a digitiser fault, moisture on the screen, or interference from a charger. Clean and dry the screen and remove any case or protector, then test again to see whether the phantom touches disappear.
Everything runs on your device
The test only reacts to the touch and pointer events the page receives; nothing is uploaded. Use the reset button to clear the canvas and start a fresh sweep.
Frequently asked questions
Slowly drag a finger over the whole test area, including the edges and corners. Covered spots fill in and the coverage percentage rises. Any region that stays blank however you swipe it is a dead zone, that part of the digitiser isn't registering touch.
Place several fingers on the screen at once. Each touch shows as its own numbered circle and the test reports the maximum number of simultaneous touches it detected. Most modern phones support 5 or 10; a lower number can mean a hardware or browser limit.
Common causes are a cracked or impact-damaged panel, a failing digitiser, water damage, or a tight case or screen protector pressing on the edges. Removing the case or protector and re-testing helps tell a hardware fault from an accessory problem.
Those are ghost touches, usually caused by a faulty digitiser, moisture on the screen, or electrical interference, often from a cheap or failing charger. Clean and dry the screen, unplug the charger, and test again to see whether they stop.
Yes. It works in the browser on any touch device (phones, tablets and touchscreen laptops) and uses pointer events, so a stylus or a touchpad works too. Nothing is installed and nothing you touch is uploaded.