Touch Screen Tester
Multi-touch point tracking and digitizer dead-zone detection.
Tap, drag, and multi-touch
Use the pad below — or open fullscreen on a phone to test every corner of the screen.
Green cells light up as you sweep. Aim for 100% so dead zones near edges and corners are less likely to be missed.
1) Single-finger sweep across the full pad
2) Hold 2+ fingers for multi-touch
3) On mobile, open Fullscreen test and tap every edge and corner
maxTouchPoints = 0). You can still click/drag with a mouse to check the UI. For a real digitizer test, open this page on a phone or tablet and use Fullscreen test.navigator.maxTouchPoints and is what the OS/browser claims, not a lab measurement. Fullscreen mode expands the pad to the full viewport (with safe-area insets) so phone edges and corners can be checked.
About this tool
Tap and drag across the test surface and this tool renders a colored circle for every active touch point in real time, reporting your device's maximum simultaneous touch capability alongside what's actually currently registered.
It listens directly to touchstart, touchmove, touchend, and touchcancel events, plotting each touch's clientX/clientY position independently — so multi-touch gestures show as multiple simultaneously tracked circles, not a single averaged point. It also reads navigator.maxTouchPoints to report your digitizer's stated hardware capability, and automatically shows a notice if the current device has no touch support at all.
Key features
- Real-time multi-touch point rendering, one tracked circle per active finger
- Live current and maximum simultaneous touch point counters
- navigator.maxTouchPoints hardware capability readout
- Automatic no-touch-support detection and notice for non-touch devices
Why use it
- Find dead zones or coordinate drift by deliberately sweeping the full screen surface
- Confirm true multi-touch gesture support, not just single-finger tapping
- Quick pre-purchase or warranty-claim check for a touch panel's real capability
Why touch screen tester testing matters
Touch digitizers can develop dead zones or coordinate drift from physical wear, screen protector interference, or driver issues — problems that are easy to miss during normal use but become obvious once you deliberately sweep the entire surface and watch for gaps in registered input.
Tips for accurate results
- Drag slowly from each corner to the center to check for dead zones near the screen edges, a common wear pattern on older digitizers.
- Try two-finger and multi-touch gestures if your device supports them, to confirm the digitizer tracks multiple points independently.
- Remove any screen protector temporarily if you're seeing inconsistent touch registration — thick or air-bubbled protectors can interfere with capacitive sensing.
- Test with both a finger and (if applicable) a stylus, since some digitizers handle each differently.
Frequently asked questions
Why does my touch feel offset from where I actually tap?
This usually points to a digitizer calibration issue. Check your OS display/touch calibration settings, especially after changing display scaling or resolution.
Does this work on a laptop trackpad?
No — this tool is built for touch-screen digitizers (finger-on-glass input), not trackpads, which use a different input pathway.