How to use
- Press Start test or hit Enter — your whole screen turns red.
- Press Space or click to go through red → green → blue → white → black. Pressing once more on the last color ends the test.
- On each color, slowly scan the entire screen. A tiny dot of a different color is a faulty pixel. Press Esc to stop at any time.
Good to know
A dead pixel is always off and shows as a black dot on white or bright screens. A stuck (hot) pixel is always on and shows as a bright or colored dot on black. The red, green and blue screens reveal sub-pixel defects where one color fails.
Backlight bleed appears as cloudy bright patches near the edges of a black screen. Check it in a dark room with brightness turned up.
Test a new monitor within the return window. Manufacturers have different pixel policies for how many defects qualify for a replacement.
FAQ
Should I press F11?
No need — F11 is your browser’s own full-screen mode. The test enters full screen automatically when you press Start or Enter.
Does it work on phones and tablets?
Yes. Tap to change colors. On browsers without full-screen support (like Safari on iPhone) the colors still fill the visible screen.
Can a stuck pixel be fixed?
Stuck pixels sometimes recover after showing rapidly changing colors for a few minutes, but truly dead pixels usually can’t be fixed. Contact the seller about a replacement.
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