Touchscreen Tester

Slowly drag a finger across the grid — every cell you touch paints green. Any cell that refuses to paint no matter how you approach it points to a digitizer dead zone. Multiple fingers are tracked separately with live coordinates, so you can also verify multi-touch works.

A mouse or stylus paints too, which makes it handy for basic pointer testing on laptops and convertibles.

Common uses

• Find dead zones on a phone or tablet screen after a drop or screen replacement
• Verify how many simultaneous touches a device actually registers
• Check that a replacement digitizer covers the full panel

Limitations

• The grid covers the browser viewport, not the areas under browser chrome or system bars — test in fullscreen for full coverage.

Is anything recorded when I test my touchscreen?

No. Touch positions are drawn onto a canvas in your browser and exist only on screen — nothing is logged, stored, or transmitted anywhere.

How do I find dead zones on my touchscreen?

Drag a finger slowly across every part of the grid; each cell paints green the moment it registers a touch. A cell that stays unpainted no matter how you approach it marks a spot where the digitizer is not responding.

How many fingers can a touchscreen track at once?

It varies by device — many phones track 10 simultaneous touches while budget panels may stop at 2 to 5. Place fingers down one at a time and watch the live touch count and per-finger coordinates to find your device's real limit.

Why can't I test the very edges of my screen?

The grid only covers the browser viewport, so areas under the address bar, system bars, or notch cutouts are unreachable. Switch the browser to fullscreen mode to bring most of the panel into the test area.

Does the tester work with a mouse or stylus?

Yes. Mouse and stylus input paints cells just like a finger, which makes the grid useful for basic pointer checks on laptops and convertibles — though that verifies the pointer, not the touch digitizer itself.