A screen color test fills your entire display with pure, solid colors one at a time. Against a clean, full-screen color, problems that are invisible during normal use become obvious — dead or stuck pixels, discoloration, color tint, dirty-screen effect and panel non-uniformity.
Cycle through red, green, blue, white, black and other solid colors below. Inspect the screen closely for any dot, patch or area that looks wrong. It works on any monitor, laptop, phone, tablet or TV browser — no download needed.