White Screen Test
A pure white, full-screen display — useful for spotting dead pixels, dust, and scratches on a monitor or phone, using your screen as an impromptu light source, or as a blank white background for photos, video calls, and presentations.
Why use a white screen test
Spotting dead and stuck pixels
A solid white background is one of the best ways to check for stuck pixels, since a stuck pixel showing red, green, or blue stands out sharply against pure white. For a dead (unpowered) pixel, white on its own isn't quite enough — pair it with the black screen test or the full dead pixel test, which cycles through all five colors automatically.
Checking for scratches, dust, and screen coating wear
Scratches, smudges, and coating wear on a screen are often invisible against normal content but show up clearly against a flat white background, especially under bright light. This is a quick way to check a used laptop or monitor before buying, or to see if a screen protector needs replacing.
Using your screen as a white light source
A full-screen white display works in a pinch as a soft, even light source — useful for quick video calls in a dim room, a makeshift ring-light effect, or extra desk lighting when you don't have a lamp handy.