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Monitor Check

Dead Pixel Test

This free dead pixel test cycles your screen through solid white, black, red, green and blue so you can spot defects fast.

Showing: White. Tap the screen to cycle colors, press Esc to exit full screen.

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Dead pixels stay black on every color; stuck pixels stay one color on black. Use fullscreen in a dim room, scan slowly, and cycle with a click or the arrow keys.

How It Works

  1. Clean the screen first so dust is not mistaken for a defect.
  2. Go fullscreen and let your eyes adjust.
  3. Start on white: dead pixels appear as black dots.
  4. Switch to black: stuck/bright pixels appear as colored or white dots.
  5. Cycle red, green, blue to catch stuck sub-pixels.
  6. Photograph any defect against the color where it's most visible for a warranty claim.

Frequently Asked Questions

What is the difference between a dead pixel and a stuck pixel?

A dead pixel gets no power and stays black on every color. A stuck pixel still lights up but is frozen on one color (usually red, green or blue).

How does a dead pixel test work?

It fills the screen with one pure color at a time so any pixel that does not match the background stands out.

Can dead or stuck pixels be fixed?

True dead pixels usually cannot be fixed. Stuck pixels sometimes respond to rapid color-cycling ("pixel exerciser") software run over the spot for 15-60 minutes.

How many dead pixels are normal?

Under ISO 9241-307 (the standard that replaced ISO 13406-2), most consumer panels fall in Class II, which permits up to 2 bright, 2 dark, and 5-10 sub-pixel defects before warranty replacement. Policies vary by brand. Dell's Premium Panel Guarantee, for example, promises "zero tolerance for bright pixels" and replaces an UltraSharp display on a single bright pixel, while standard monitors follow the ISO Class II thresholds.

More Color Screens

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