Screen Test
Check your monitor or display for dead pixels, stuck pixels, and backlight bleed by cycling through full-screen solid colors.
Click "Next Color" to cycle through each test color. Look closely for any pixel that doesn't change color, or any patch that looks brighter or dimmer than the rest.
Screen Test FAQ
More free diagnostic tools
Press any key to verify it registers, measure hold time in milliseconds, and confirm N-Key Rollover — entirely in your browser, with zero data leaving your device.
Check your phone, tablet, or touchscreen laptop for multi-touch support, dead spots, and responsiveness — tap anywhere below with one or more fingers.
Check that your webcam works, preview your live video feed, and verify its resolution — all in your browser, with nothing ever uploaded or recorded.
Check that your microphone works and see your live input level — all in your browser, with nothing ever uploaded or recorded.
Type the passage below as quickly and accurately as you can to measure your typing speed in words per minute (WPM).
Check that your left and right speakers or headphone channels both work correctly by playing a test tone to each one individually.
Connect a controller and press any button to verify every input works — buttons, triggers, and both joysticks.