Dead vs stuck pixels: how to tell them apart with five colors

How this is calculated

Each solid color asks the panel to do one simple thing. White turns every subpixel fully on, so a dead pixel shows as a black dot. Black turns every subpixel off, so a stuck subpixel shows as a bright red, green or blue dot, and a fully stuck pixel shows as white. The single color fills are the most useful step people skip. On red, only the red subpixels are lit, so a dead red subpixel shows as a dark dot that might be invisible on white, since its green and blue neighbors still glow. Go through all five and note which colors show the dot and which don't. That tells you the fault and the subpixel. Before you call it a fault, rule out dust and debris. Wipe the screen gently with a dry microfiber cloth, without pressing, and look again from a slight angle. Dust on the surface casts a soft shadow and moves when you shift your head, while a pixel fault stays sharp and fixed in the grid. Hide the test controls with H or a tap, since they cover part of the screen, and check the corners as carefully as the center. A magnifier or your phone's camera zoom helps on high density panels, where a single subpixel is tiny.

Verdict

Run all five colors, not just white and black, and confirm anything you find a second time after wiping the screen. A single stuck subpixel near the edge is often easy to live with, while a dead pixel in the middle of your view usually isn't. Makers handle this differently, so check the pixel policy for your model before you decide. Avoid pixel fixing videos with rapid flashing. They're a seizure risk and rarely fix anything.