UsefulTab
Screen Test
Fill your screen with solid colors and patterns to check the display.
Test your monitor or display
Screen Test fills your whole display with a solid color or pattern so problems that hide behind normal content become obvious. Press a color to fill the test area, and use Fullscreen for an edge-to-edge check. Solid white and grey reveal uneven brightness and, in a dark room, the "backlight bleed" some LCD panels show at the edges. Solid red, green, and blue make stuck sub-pixels of that color stand out. Black helps you spot always-on (bright) dead pixels. The gradient checks for banding — a good panel shows a smooth fade rather than visible steps. Click or press a key to advance through the colors, or Escape to leave fullscreen. Everything runs in your browser; nothing is uploaded.
Common questions
How do I run a full-screen test?
Press Fullscreen to fill the entire display, then click or press any key to cycle through the colors and patterns. Press Escape to exit fullscreen at any time.
What does each color check for?
White and grey show brightness uniformity and backlight bleed; red, green, and blue reveal stuck sub-pixels of that color; black exposes bright (always-on) dead pixels; the gradient checks for banding — a smooth fade means good color depth.
What is backlight bleed?
On LCD panels, light can leak around the edges, most visible as lighter patches when the screen shows solid black or dark grey in a dark room. A little is normal; large bright patches indicate a panel issue.
What is the difference between this and the Dead Pixel Test?
They overlap. Screen Test is a broad monitor check (uniformity, bleed, banding, and pixels). The Dead Pixel Test focuses specifically on cycling solid colors to hunt for individual dead or stuck pixels.
Is anything uploaded?
No. The colors are drawn by your browser locally. Nothing about your screen or the test is stored or sent anywhere.