How to test a touchscreen before a device trade-in

Before you trade in a phone or tablet, check that the whole screen responds to touch. A missed tap near an edge or a patch that does not respond can affect the device’s condition and the value you are offered.

Use the Touch Screen Test on the device you plan to trade in. It checks touch points, multi-touch input and areas that may not respond, so you can find and describe a problem before handing the device over.

Test the touchscreen

1. Open the Touch Screen Test on the phone or tablet you are checking. Run the test on that device, not on a computer connected to it, because the test needs to receive its own touch input.
2. Set the device on a stable surface and wipe the screen with a clean, soft cloth. Remove gloves and make sure your fingers are dry. If the screen is cracked, do not press hard on it.
3. Move one finger slowly across the entire test area. Cover the center, edges and corners in overlapping passes. Watch whether the displayed touch point follows your finger continuously, or disappears or jumps in a particular spot.
4. Touch separate parts of the screen at the same time to check multi-touch. The test can show whether it detects multiple contact points. Use light pressure and avoid pressing a damaged screen.
5. Repeat the checks with the device held in its usual portrait and landscape positions. Note the location of any missed or erratic input, and whether it happens every time.

For a small defect, test the same area several times. A single missed touch can come from a damp finger, a smudge or an accidental brush against the screen. A repeatable patch is more useful evidence when you describe the device to the trade-in company.

What the result means

Touch points follow your finger across the screen

The screen is registering touch in the areas you tested. This is a good sign, but it does not prove that every app gesture or every part of the digitizer works under all conditions. Check the screen again after using the device normally for a few minutes, especially if the problem you noticed happens only while typing or scrolling.

A spot repeatedly misses touches

A consistent blank patch may be a touchscreen dead zone. Repeat the test after cleaning the screen and, if it is safe to do so, removing the case or protector. If the same area still fails, note its position and include it when reporting the device’s condition. For more examples of dead zones and how they appear, see how to find dead spots on a touchscreen.

The touch point jumps or appears away from your finger

This can happen because of moisture, a screen protector, a charging accessory or a software problem. If it continues after the quick checks below, test again with the device unplugged. An inaccurate response that remains in the same area may point to a screen or digitizer fault.

Multi-touch does not register as expected

The browser test can show the contact points it receives, but it cannot confirm that every app’s pinch, rotate or other gesture will work correctly. If the test detects several fingers but a particular app does not respond to a gesture, the issue may be in that app or its settings rather than the screen.

How to fix or rule out common causes

1. Clean and dry the screen. Wipe off oil, dust or moisture, then try again with dry fingertips. Do not spray cleaner directly onto the device or use a rough cloth.
2. Check the case and screen protector. A lifted edge, crack or trapped dirt can interfere with input. Remove an accessory only if you can do so safely. Do not peel off a protector that is holding cracked glass together.
3. Unplug the charger and accessories. Test the screen without a charger, hub or connected accessory. If erratic touches stop when unplugged, try a known-good charger and cable before blaming the screen.
4. Restart the device. A restart can clear a temporary software problem. After it starts, reopen the test and check the same locations before changing other settings.
5. Check touch-related settings. On an iPhone, open Settings › Accessibility › Touch and review options that change how long or where a touch must land. Android menu names vary, so open Settings › Accessibility and look for touch or interaction options. On Windows 11, check Settings › Bluetooth & devices › Touch if that page is available on your device. Macs do not have built-in touchscreens or a general macOS touchscreen setting; for a touch display connected to a Mac, follow the display maker’s instructions.
6. Install system updates. If the problem began after an update or has no clear pattern, install available updates and test again. On Windows 11, open Settings › Windows Update. On macOS, open System Settings › General › Software Update. On a phone, use its system update page, whose location varies by model.

When it may be a hardware fault

If the same area fails in the test after cleaning, restarting and removing accessories, the screen assembly or its touch sensor may be damaged. A crack, recent drop, pressure mark or liquid exposure makes hardware damage more likely. A browser test can show where touch input is missing, but it cannot identify the failed component or confirm the cost of repair.

Before trading in the device, check the provider’s condition rules and describe any repeatable fault honestly. If the device is still under warranty, ask the manufacturer or seller about inspection before paying for a repair. Compare the repair estimate with the trade-in offer, since replacing a screen may cost more than the difference in value.

Keep a clear record before you hand it over

Write down the affected area, the orientation you used and whether the problem happened more than once. If you take a photo or video as evidence, make sure it does not show notifications, messages or other personal information. Complete your backup and the device maker’s erase or factory reset steps only after testing and recording the issue. A touch test checks input response; it does not erase or inspect your personal files.