A touch screen test tells you instantly whether every part of your display responds — critical when buying a used iPhone or iPad, or diagnosing one after a drop or screen replacement. This tool turns your whole screen into a drawing surface: wherever your finger registers, a line appears. Any patch that stays blank as you sweep across it is a dead zone.
It also verifies multi-touch. A live counter shows how many fingers the digitiser sees at once and records the maximum — an iPhone should register up to five, an iPad up to eleven. A replaced or failing digitiser often drops touches or caps below that. Everything runs locally in your browser, so there’s nothing to install.
How to use it
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1Start the test
Tap “Start touch test” to open the full-screen drawing surface with a reference grid.
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2Sweep the entire screen
Drag one finger slowly across every area — edges and corners included. A continuous line should follow. Gaps mean unresponsive spots.
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3Check multi-touch
Place several fingers down at once and watch the counter. Note the maximum it reaches: 5 on iPhone, up to 11 on iPad. Dropped touches point to a digitiser fault.
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4Clear or exit
Tap “Clear” to wipe the canvas and test again, or “Exit” to return. Nothing is saved.
Why This Test Exists
Isolating hardware from software is the whole point. On a device running pre-release software, every fault gets blamed on the beta, and most of the time that is wrong. A test that exercises the hardware directly turns "something is broken" into something specific enough to act on.
Getting a Reliable Result
Run the test twice — once as the device is now, once after a restart. A fault that survives both is worth investigating; one that clears is almost always software.
Reading the Outcome
If the result points at software rather than hardware, our beta troubleshooting guides cover what to do next.
Nothing Leaves Your Device
This tool runs entirely in your browser. There is no upload step, no account, no cookie set for it and no record kept of anything you test — which is a consequence of how it is built rather than a policy you have to trust. It also means it works on any device, on any operating system version, whether or not you are running a beta.
If a test here points at software rather than hardware, that is useful in itself: it means the next step is a beta build or a setting rather than a repair. Our troubleshooting guides cover the common ones, and your device's page sets out what to expect from your specific model on the current release.
Frequently asked questions
How do I find a dead zone on my iPhone screen?
Start the test and drag one finger slowly across the entire display in overlapping passes, including the very edges and corners. The line should never break. Any area where your finger moves but no line appears is a dead zone — a spot the digitiser no longer registers.
How many fingers should multi-touch detect?
iPhones support up to 5 simultaneous touches and iPads up to 11. Place that many fingers on the screen and watch the live counter. If it caps lower or flickers, the digitiser may be failing or was replaced with a non-genuine part.
Is this a good way to test a used iPhone before buying?
Yes. Dead zones and multi-touch faults are among the most common hidden problems on used and repaired devices, and they’re hard to notice in casual use. A one-minute sweep of the whole screen here reveals them immediately.
Does it store what I draw?
No. The drawing exists only on the screen in front of you and is discarded the moment you clear or exit. Nothing is uploaded or saved.