Touch screen test
Drag one finger over every square. Squares that never light up show where the screen did not register your touch.
Touch screen test workspace
How to use
4 short steps.
Touch the grid or go full screen
Tap Full screen for the biggest grid, then start dragging. The test begins on your first touch.
Paint every square
Use slow, overlapping strokes across rows, edges, and corners until every square turns blue.
Retry blank squares
Approach a blank square from another direction. Clean the screen and take off a thick case or protector first.
Read the result
When every square is painted the test passes. Squares that stay blank after several tries point to a dead zone.
What the result means
Match what you see to one of these.
If every square paints, the screen registers touch everywhere
Your touch screen passed. A problem that only shows up in one app is a software issue, not the screen.
If the same squares stay blank from every direction, suspect a dead zone
Screenshot the grid. A repair shop or the manufacturer's diagnostic can confirm a faulty area of the digitizer.
If squares paint while your finger is elsewhere, that is ghost touch
Unwanted touches usually come from a damaged screen, a poor protector, moisture, or a faulty charger.
If strokes near the edge stop early, the system took the gesture
Back, home, and notification gestures cancel touches at the edge. Start strokes a little inside the screen.
Troubleshooting
If the test fails, try these in order.
Clean and dry the screen
Wipe the glass, dry your fingers, and remove a cracked or bubbled screen protector. Paint the blank area again.
Unplug the charger
A cheap or damaged charger can cause missed and phantom touches. Test on battery and retry the grid.
Restart the phone
A restart clears a stuck touch driver. Open this page again and repaint the whole grid.
Try the maker's diagnostic
Samsung phones open a touch test from *#0*# in the dialer. If the same area fails there too, book a repair, then retest here.
What this test can't tell you
Where a browser check stops.
- The grid shows where the browser received touch. It cannot measure touch accuracy, sampling rate, or latency.
- System gestures, pointer cancellation, cases, protectors, moisture, zoom, and orientation all affect which squares paint.
- A blank square points to a dead zone but does not prove one. Confirm it in the maker's diagnostic before paying for a repair.
FAQ
Common questions about this test.
How do I check if my touch screen is working?
Drag a finger over the grid on this page. If every square paints, the screen registers touch everywhere. If some stay blank after several tries, that area is not responding.
What is a touch screen dead zone?
A dead zone is an area of the screen that ignores touch. On this grid it shows as squares that never paint no matter how you approach them.
What is ghost touch and how do I test for it?
Ghost touch is when the screen registers taps you did not make. Watch the grid with your hands off the screen. Squares that paint by themselves are ghost touches.
Why does my touch screen act up while charging or with wet fingers?
Water and sweat conduct electricity and confuse the sensor, and a poor charger adds electrical noise. Dry the screen, unplug, and retest.
What is the Samsung touch screen test code?
Dial *#0*# on many Samsung phones and choose Touch. This page does the same job on any phone or tablet with a browser.