Blue Screen
Fullscreen tool for display testing. Works in-browser, no signup.
Blue
Pure blue — isolates dead blue sub-pixels. The dimmest of the three channels.
Press Esc to exit
About this tool
Full blue channel at maximum intensity. Blue is the dimmest channel to the human eye, so this screen looks less bright than red or green — that's normal. Any bright non-blue dots are faulty sub-pixels.