Dead pixel test

How to check your screen for dead pixels

1. Wipe the screen with a dry microfibre cloth so dust is not mistaken for a pixel.
2. Press Start pixel test. The screen fills with black.
3. Click, press Space or → to go to the next colour; ← goes back. Scan the screen in strips, from one edge to the other.
4. When you find a suspicious dot, check whether it stays the same on every colour.
5. Press Esc to exit.

Dead, stuck or hot pixel?

• Dead pixel: always dark. Most visible on the white screen.
• Hot (bright) pixel: always lit, usually white. Most visible on the black screen.
• Stuck pixel: stuck on one colour — red, green or blue, or a mix. It shows on the colours that do not contain it, for example a green dot on the red and blue screens.
• Dust or a mark: looks the same on every colour, sits on the surface, and shifts or blurs when you look at it from an angle.

Note where the defect is and on which colours it appears. A photo of the screen with the colour that shows it best is useful for a return or warranty claim.

Limits

• The page draws colours; it cannot detect a defective pixel by itself. You are the detector.
• Browser zoom, night-light filters, HDR tone mapping and TV picture modes can change how the colours look. Turn them off while testing.
• On phones that do not allow web pages to go full screen, the browser bars stay visible. Scroll or rotate to see the edges.
• Flashing colours do not repair pixels. Stuck pixels sometimes recover on their own; dead pixels do not.