Touch Screen Test

How this test works

Draw across the full screen and tap the edges to reveal missed or interrupted touch input.

1. Prepare the display using the checklist below.
2. Select Start test and allow fullscreen mode if your browser asks.
3. Use the arrow keys, on-screen controls, or click the pattern to move through the test.
4. Exit the runner and save a local observation if useful.

Before you begin

• Clean and dry the screen
• Remove gloves unless the display supports them
• Place the device on a stable surface

What to look for

• Gaps while dragging a finger
• Edges or corners that do not respond
• Incorrect or missing simultaneous touches

Trace the surface in a repeatable path

The touch runner records pointer activity delivered to the browser as you draw across the screen. Start with a clean, dry surface and a stable device. Trace slow horizontal and vertical paths through the center, then visit each edge and corner. Look for a gap that repeats in the same location instead of one line that broke when your finger lifted. If the page supports the device’s simultaneous contacts, place several fingers down and watch whether the browser receives the expected count. The result describes browser-delivered touch events, not an electrical map of the digitizer.

Use a normal finger contact rather than a glove or stylus unless your device is designed for that input. Repeat a suspected gap from another direction and at a slower speed. A missed segment near an edge may be caused by an operating-system gesture taking control before the browser receives the event. Browser chrome or a screen protector can also change where your finger makes effective contact. Document the physical area and the exact action that fails instead of calling the entire display unresponsive after one incomplete trace.

Understand what the browser can see

The page sees pointer events that the browser and operating system choose to deliver. It cannot measure pressure accuracy, sensor sampling rate, input latency, or physical electrode health. Palm rejection, accessibility settings, device drivers, screen rotation, zoom, and reserved edge gestures all influence the input path. A device may register taps in another app but not in the browser if an overlay or gesture intercepts them. Conversely, a clean browser trace does not guarantee every application will handle touch correctly.

For a multi-touch check, try two contacts before using more. Watch whether both appear and stay separate while you move them. A missing contact can reflect a device limit, an operating-system gesture, or the browser’s event handling; this test alone cannot identify which one. If the issue occurs only with a case, cover, or protector installed, record that condition and compare again after following the maker’s safe guidance. Do not apply excessive pressure to force a response.

Turn a gap into a useful report

If a zone consistently fails, repeat the same stroke with a different finger, in the opposite direction, and after restarting the browser. Note the device orientation, browser, zoom, protector, and whether an edge gesture appeared. Compare with an ordinary app that accepts drawing or touch in the same region. A result limited to one browser or one app may call for software troubleshooting rather than an immediate hardware return, while a gap across apps deserves a closer look at the device and warranty.

A screenshot cannot capture a touch path that never reached the browser, but a short video or a written map of repeated misses can document the behavior. Do not upload raw paths or coordinates unnecessarily; this test keeps the observation local by default. The page is intended to reveal coverage and continuity in a practical way, not to certify a touchscreen against manufacturing tolerances. For pixel or color issues, use the display-pattern tools instead of treating touch input as a visual panel test.

Frequently asked questions