Pixel Check

Dead pixels, stuck pixels, bleed and tint

  1. Clean the screen and set brightness to maximum. A dim room helps for the dark screens.
  2. Start the test. It fills the whole screen with one colour at a time.
  3. Look slowly across the screen, from about a hand’s length away. Tap, click or press → / Space for the next screen, ← to go back, Esc to stop.

What to look for

Dead pixel: a dot that stays black on white and colour screens. Stuck pixel: a dot that stays red, green or blue on the black screen. Hot pixel: stays white on black.

Backlight bleed and clouding: brighter patches or glowing edges on the black and dark-grey screens. Some is normal on LCDs; OLEDs should be pitch black.

Tint and uniformity: the greys should look the same colour everywhere, with no pink, green or yellow areas. Banding: the ramps should be smooth, without visible steps.

Phones and laptops may lower brightness or tint the screen automatically; turn off night mode and adaptive brightness for a fair look.