06 / TOUCHSCREEN

Check finger coverage and simultaneous touches.

Trace the test area, revisit gaps and try a 20-second hands-off check.

Local · on this device
  1. 01Choose a stable position and orientation
  2. 02Trace with a finger, then revisit gaps
  3. 03Review and keep a local report

Use a clean, dry finger. Expand the area before starting if you want more room. Only the outlined surface is measured; controls and browser bars are outside it.

Setup and notes (optional)

Notes stay local and are included when you download the report.

Ready. Start coverage or prepare a separate hands-off check.

TEST AREA / 16 × 24 GRID

Start coverage, then trace horizontal and vertical lines with a finger.

Area reached by touch0 / 384
Touches now / maximum0 / 0
First pass—

Only received touch positions fill cells. A drawn trail can cross an unchecked cell. Mouse and pen remain previews; browser bars are outside this area.

Results stay in this page until you clear, reload or leave it. Download a report to keep a copy. A language switch can carry a closed result once in this tab for up to two minutes.

Prepare the screen and your position

Open this page on the touchscreen you want to check. Use a clean, dry finger and follow the device maker’s screen-cleaning instructions. Keep the device stable and choose the orientation you want to test before starting. An expanded or fullscreen area, where available, lets you reach more of the page; browser bars and system gesture areas remain outside the tested surface.

1. Trace coverage, then recheck gaps

Move one finger slowly across the test area in overlapping horizontal lines, then vertical lines. Include the reachable edges and corners. The grid records cells reached by touch events during this run. A filled cell means a touch reached that part of the page at least once.

Go back over any empty strip or cell from a different direction. An area you did not reach is still unchecked. If a gap keeps appearing while your finger crosses it, record the location and repeat in another application or the device’s own diagnostic. Compare the same physical part of the screen.

2. Compare simultaneous touches

Place two fingers on the surface at the same time, then add more if comfortable. Spread them apart so you can see the individual contact markers. The count describes contacts active together in this browser, and the maximum is the highest count observed in this run. Try the gestures you normally use afterward.

A system gesture can take control of a contact before the page receives it. The observed maximum therefore describes this test session; use the device specification for its advertised contact limit.

3. Run the 20-second hands-off check

Choose Prepare hands-off check, then Start. Lift every finger during the two-second preparation and leave the device untouched for the full 20-second observation. Keep hands, cables and other objects away from the test surface. The tool records touch contacts received during that period so you can investigate unexpected input, often called ghost touch.

If the count stays at zero, unexpected touch was not reproduced during that check. If a contact appears, repeat under the same conditions and note what was connected to the device. Deliberately touching the surface during the interval also creates a contact, so keep that separate in your notes. Interrupted and cancelled checks keep their partial duration in the result.

If the browser cancels an input, repeat the check. Cancelled input has its own result label so you can distinguish it from received contacts.

Read the coverage and hands-off results

Result state How to use it
No input Start a coverage run with a finger on the touchscreen to collect input.
Mouse preview You tried the interaction with a mouse. Use a finger on the touchscreen to fill coverage cells; pen input also stays separate as a preview.
Touch coverage Review reached and unreached cells, repeatable gaps and simultaneous contacts together.
Hands-off result Keep the observed contacts and completion state with the conditions of that check.

Download the local report before resetting or leaving. If you rotate the device, resize the test area or leave the active page, follow the tool’s interruption message and restart the affected check with stable conditions. Review local data and language switching for how the working session is handled.

When an area keeps missing touches

For an iPhone or iPad, Apple’s touch troubleshooting starts with restarting, a clean screen and checking connected accessories or screen covers. For Windows devices, Microsoft recommends restarting and checking updates. Follow the guidance for your model and keep the repeatable location and conditions when asking for support.

For a visible mark rather than missed input, use screen inspection. Read how touch events become the report.