Dead Pixel Test

What to look for

• Dead pixel: a pixel that stays black on every colour. Best seen on the white screen.
• Stuck pixel: a pixel that stays one bright colour (red, green or blue). Best seen on the black screen.
• Hot pixel: a pixel that stays white. Best seen on the black screen.
• Get close to the screen and clean it first. Dust and smudges can look like pixel faults.

Can stuck pixels be fixed?

Stuck pixels sometimes recover if left on a flashing colour screen for a few minutes. Dead pixels are physical damage and usually cannot be repaired. Check your warranty, since many makers replace screens above a set number of faulty pixels.

How this dead pixel test works

The test fills your whole screen with one solid colour at a time: black, white, red, green, blue, yellow, cyan and magenta. A healthy screen shows a perfectly even colour. A faulty pixel stands out as a dot that does not match everything around it. Press Space or click to move to the next colour, and Esc to leave full screen.

Which colour shows which fault

• Black screen: reveals stuck or hot pixels that are lit when they should be off, as well as backlight bleed at the edges of an LCD.
• White screen: reveals dead pixels, which show as small black dots, and dirt or marks on the panel.
• Red, green and blue: reveal faulty sub-pixels. A dot that is missing on one colour only is a stuck sub-pixel.
• Yellow, cyan and magenta: reveal uneven colour or tint across the display.

Tips for a fair result

Clean the screen first with a soft, slightly damp cloth, because dust looks like a dead pixel. Dim the room lights, set the brightness to maximum, and look closely at each colour for a few seconds. On a phone or tablet, hold the device about 20 cm from your eyes.

Testing a phone?

There is a dedicated phone screen test with notes on OLED burn-in. If your touch screen also misbehaves, check it with the touchscreen test.

Last updated: 2026-10-04