Touch Screen Test

Touch Screen Test shows what a touch screen can do and where it fails. At the top it reports what the browser says about the device: whether there is a touch screen, how many fingers it can track at once, and whether a mouse, trackpad or pen is connected too. Below is a touch area. Every finger you put on it gets a numbered circle in its own colour, so you can see at a glance whether the screen keeps up with two, five or ten fingers, and the page counts the most fingers seen at once. Each finger also leaves a coloured line where it moves. Draw slowly across the whole area, top to bottom and side to side: a gap in a line that you drew without lifting your finger is a spot where the screen did not respond — a dead zone in the touch layer (the digitizer).

1. Read the line at the top: it says whether the device reports a touch screen and how many touch points.
2. Put one finger, then several, on the touch area; each gets a numbered circle. Compare “Most at once” with what the device reports.
3. Draw slow, overlapping lines over the whole area without lifting your finger, and look for breaks in the lines.
4. Press Clear the drawing to start over. Turn the device to test the other orientation too.

• The touch area is the part of the screen under it, not the whole screen: the edges, the status bar and the browser’s own bars belong to the system and the browser. Scroll and turn the device to bring other parts of the screen under the area, or use the browser in full screen.
• The number of touch points is what the browser reports. Some screens report more than they track reliably, and a few laptops report touch with no touch screen fitted.
• Pressure is shown only where the hardware sends it, which most finger touch screens do not; a pen often does.
• System gestures (swiping from an edge, three-finger gestures on some phones and tablets) may be taken by the system before the page sees them.
• A gap can also come from moving faster than the screen reports; draw slowly before deciding a spot is dead.
• Touches are read and drawn by this page in your browser and are not recorded or sent. The drawing is not saved; clearing it or leaving the page removes it.

Draw slow lines across the touch area without lifting your finger, in rows and then in columns, overlapping a little. If a line breaks in the same place each time, that part of the screen is not registering touch.

The line at the top shows the number the browser reports, usually 5 or 10. Put that many fingers on the area and check “Most at once” to see whether it really tracks them all.

Yes. Leave the device on a table without touching it. Any circle or line that appears is a ghost touch — often caused by a damaged screen, a poor screen protector, moisture, or a charger with electrical noise. Try unplugging the charger.

Yes, in any recent browser. A trackpad is not a touch screen: it moves the pointer, so it shows as a mouse, not as fingers.