How to test for dead pixels
- Clean the screen with a soft, dry microfiber cloth so dust is not mistaken for a defect.
- Set brightness to maximum and disable night mode or color filters.
- Click Start Full-Screen Test and step through all eight colors.
- On each color, scan the whole screen at close range, including corners and edges.
- Note the color(s) where any dot looks wrong. The pattern tells you the type of defect.
What each color reveals
Black exposes pixels stuck on. White exposes pixels that are off. Red, green and blue isolate individual subpixels, and cyan, magenta and yellow confirm combinations of them. A dot that is visible on only one or two colors usually means a stuck subpixel, while a dot that stays black on every color is dead.
Frequently asked questions
How to test for dead pixels?
Clean your screen, set brightness to maximum, and start the full-screen test. Step through white, black, red, green, blue, cyan, magenta and yellow. On each solid color, look closely for any tiny dot that stays a different color or stays dark or bright.
What is the difference between a dead and stuck pixel?
A dead pixel is permanently off and shows as a black dot on every color, caused by a failed transistor. A stuck pixel is always on and shows as a fixed red, green, blue or white dot. Stuck pixels can sometimes be fixed; dead pixels usually cannot.
Can a stuck pixel be fixed?
Often, yes. Rapidly flashing colors over the affected spot for 10 to 30 minutes can free a stuck subpixel. Success is not guaranteed, and true dead pixels are generally permanent.
Is PixelCheck free and private?
Yes. PixelCheck is free and runs entirely in your browser. No data is uploaded and no account is needed.
How many dead pixels are acceptable?
It depends on the manufacturer's pixel policy, commonly based on the ISO 13406-2 classes. Many warranties cover a monitor only when several defective pixels are present. Check your brand's policy before returning a display.