WhitestScreen
Active touches0
Max this session0
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Mode

Touch Screen Test

By , WhitestScreen.com

Tap or drag anywhere on the panel above to test your screen's touch response. Grid mode lights up each cell you touch, so any square that never lights up despite repeated taps is a candidate dead zone. Draw mode traces your finger so you can spot skipped segments or jitter. Touch points are tracked live at the top, which is the easiest way to check your device's real multi-touch support.

How to use it

  1. Go fullscreen for full coverage, since a non-fullscreen browser leaves the address bar and toolbar covering exactly the edges where dead zones are most common.
  2. In Grid mode, systematically tap every cell, corner to corner, including the very edges.
  3. Try placing several fingers down at once and check the "Active touches" and "Max this session" counters against what your device should support.
  4. Switch to Draw mode and trace slow curves and fast zig-zags. A smooth, unbroken line means healthy tracking; skipped or jumpy segments are worth re-testing on a clean, dry screen.
  5. Tap Clear to reset the grid and canvas between passes.

Frequently asked questions

What counts as a touch dead zone?
A dead zone is an area of the screen that doesn't register touch input at all, even though the display itself shows an image fine there. In grid mode, any cell that never lights up no matter how many times you tap it is a candidate. Try it a few more times before concluding it's a real dead zone, since a single missed tap can happen on a perfectly healthy screen.
How many touch points should my screen support?
Most modern phones support 5 to 10 simultaneous touch points, and most tablets and laptops support 10. iPhone reports 5 touch points at the system level even though the hardware can sense more. If your device supports fewer simultaneous touches than expected for its category, that's worth noting, though it's not necessarily a defect, since some manufacturers cap it intentionally.
Does this detect stylus pressure?
If your stylus and browser support it, yes. Pressure and tilt appear in a small readout when you use it. Finger and mouse input don't report meaningful pressure data, so the readout only appears for real stylus input.
What causes jitter or jumping when I draw on the screen?
A wet or dirty screen is the most common cause, since capacitive touch works by sensing tiny changes in electrical charge, and moisture disrupts that signal. Electrical interference from a cheap charger can also cause drift or ghost touches. If jitter persists on a clean, dry screen away from a charger, it may point to a digitizer issue worth having checked.

Testing a brand-new device? A touch dead zone belongs on the same checklist as a dead pixel. See our new monitor defect checklist for the full return-window walkthrough, or head to the Dead Pixel Test to check the display itself.

Not sure this is your actual problem? Start with the full screen defect triage guide →

The dead-zone grid marks a cell only after your browser actually reports a touch event there, so any gap in coverage reflects the touchscreen's own event reporting rather than a guess. Multi-touch and jitter detection rely on the same Pointer Events data any web page can read, checked against how touchscreen diagnostics are commonly run today.

About the creator

Ready Utilities was founded by Cedrick Reese, a retired veteran and web developer who enjoys building free, user-friendly online tools that simplify everyday tasks. Read more →