Drag your finger across a fullscreen grid to find spots on the screen that no longer respond to touch.
Cells you touch get filled in. Any cells left blank mark where the screen may not respond.
Touch with several fingers at once to see how many points are recognized and where.
Draw freely to spot line breaks and ghost touches by eye.
⚠️ An unresponsive spot does not by itself mean the device is broken (it may be a temporary glitch or a screen protector).
Your browser does not support fullscreen, so the browser UI stays on screen and the fullscreen touch area is only a rough guide. The test still runs.
🔒 Everything runs on your device — nothing is sent or saved.
Before you sell a phone or tablet, or right after buying one used, checking the screen and inputs helps avoid disputes. Common things to verify:
A problem you find does not always mean a fault or defect. A temporary software glitch, a screen protector, or dirt can cause similar symptoms, so try a restart and check the protector before deciding.
If these symptoms happen repeatedly in the same fixed spot, the touch sensor there may have an issue. But a lifted screen protector, dirt, static, or a temporary software glitch can produce similar symptoms, so this tool\'s result alone cannot confirm a fault. If you are concerned, remove the screen protector and re-check, restart the device, and then contact the seller or manufacturer support.
Pick one of the three tests and press "Start fullscreen". In the grid test, drag your finger across the whole screen and try to fill every cell — any cells you cannot fill mark spots that respond weakly or not at all. The multi-touch test shows how many fingers are recognized at once, and the draw test lets you look for lines that break up or dots that appear where you did not touch.
A dead touch zone is an area of the screen that responds slowly or not at all when you tap or swipe over it. It can be caused by wear or damage to part of the digitizer or display, by a lifted or dirty screen protector, or by a temporary software glitch. Because the cause is not always the hardware, use this tool to find whether an unresponsive area exists — not to diagnose a fault by itself.
Ghost touch is when the screen registers input on its own, without your finger. In the draw test, if lines or dots appear where you did not touch, that suggests ghost touch. Static, charger noise, or water and grime on the screen can trigger it temporarily, so try unplugging the charger, wiping the screen, and restarting before deciding whether it keeps happening.
Not necessarily. An unresponsive spot can come from a temporary software issue (a restart sometimes clears it) or from a screen protector or dirt on the glass. Try restarting the device and removing the screen protector first. If the same spot still does not respond, contact the seller or the manufacturer's support.
Yes. A lifted protector, trapped air bubbles, or dust and grime caught under the edges can reduce touch sensitivity in that area. If the unresponsive spot lines up with the edge or a seam of the protector, peel the protector off and check the same spot again. If it works once the protector is off, the device itself is not at fault.
You can fill the grid with a mouse, but this tool is meant for checking the touchscreen of a phone, tablet, or other touch device. To check a computer monitor itself (dead or stuck pixels), use the Monitor Test instead.
Use the "×" button in the top-right corner to quit. If that does not work, press the Esc key (if you have a keyboard). Esc is kept as a fallback in case a dead touch zone stops you from pressing the button. Going back in the browser or closing the tab also ends the test.
Prefer the Japanese version? タッチパネルテスト（日本語版）
