Dead pixel test

A dead pixel receives no power, so it stays black on every color and is most visible on the white screen. A stuck pixel has one or more of its red, green or blue subpixels permanently on, so it shows as a bright red, green, blue or white dot, most visible on the black screen. A hot pixel is a stuck pixel that is fully white. Stuck pixels can sometimes be revived; truly dead ones usually cannot.

Black reveals stuck and hot pixels and backlight bleed along the edges. White reveals dead pixels and uneven brightness. Solid red, green and blue each isolate one subpixel, so a dot that is dark on red but fine on green and blue points to a failed red subpixel. The gray screen is good for spotting dirty-screen effect, banding and tinted patches on OLED and VA panels.

Sometimes. Rapidly cycling colors forces the pixel’s subpixels to switch on and off, which can free a liquid crystal that has stuck in one state. Reported success is mixed: it tends to work on pixels that became stuck recently and rarely helps on pixels that have been stuck for months or that are completely dead. Run it for 10 to 20 minutes, and try again a few times before giving up. It will not harm the screen.

The fixer flashes rapidly changing colors, which can trigger seizures in people with photosensitive epilepsy and can be uncomfortable for anyone. Do not look at it directly while it runs — position the square, then look away or leave the room. The fixer never starts on its own; you must confirm the warning first. The full-screen color test itself does not flash.

It depends on the manufacturer’s pixel policy, most of which follow the ISO 9241-307 pixel fault classes. Many brands only replace a monitor once it has several faulty pixels, while some premium lines promise zero bright (stuck) pixels. Test a new screen within the return window, photograph any fault with the solid color behind it, and check the warranty’s pixel policy before contacting the seller.