Monitor Test — Check Any Screen for Dead & Stuck Pixels
Fill your screen with solid white, black, red, green, blue and gray to spot dead or stuck pixels — plus a flashing fixer that may revive stuck ones.
Processed entirely in your browser — nothing you enter here is ever uploaded.
Result
About this tool
This page opens the full monitor test: press start and step through white, black, red, green, blue and gray in fullscreen, looking for any dot that refuses to match the color around it.
Run it whenever you want a general health check on a display — a new monitor fresh out of the box before the return window closes, a second-hand laptop or phone you are about to buy, or a screen you have used for years and simply want to look over. Each color exposes a different kind of defect, so cycling through all of them catches more than checking just one.
If a swatch turns up a stuck (colored) point rather than a dead (always black) one, switch over to the stuck-pixel fixer mode from the same tool — it is worth a try before assuming the worst. Everything runs locally in your browser: no download, no install, no account.
Example. Choosing the red swatch paints the full-screen overlay #ff0000.
Limit. The flasher cycles five colors and never reads pixels back, so it cannot report a dead-pixel coordinate.