Monitor Test

This tool runs four display diagnostics in your browser to check an LCD/OLED panel for uniformity, color accuracy, contrast, and stuck or dead pixels. It renders full-screen solid fills, gradient sweeps, and a grayscale contrast ladder directly on the monitor you are testing, so issues like backlight bleed, banding, or defective subpixels become visible.

1. Pick one of the four test cards: Color Test, Gradient Test, Dead Pixel Test, or Contrast Test. 2. In the Color Test, tap any of the eight swatches (Red, Green, Blue, White, Black, Yellow, Cyan, Magenta) to inspect for tinting or uniformity problems. 3. In the Dead Pixel Test, click a swatch to enter a fullscreen solid color so you can scan for stuck pixels; clicking anywhere exits back to the swatch grid. 4. The Contrast Test shows white-on-black and black-on-white blocks, four gray fills (25%, 50%, 75%, 90%), and a readability sample with visible and not-visible markers.

The Color Test exposes eight pure-channel fills that reveal color cast and uniformity. The Gradient Test draws five multi-stop sweeps (a full RGB hue ramp, a black-to-gray ramp, and three accent gradients) that expose banding on 6-bit or poorly calibrated panels. The Dead Pixel Test uses the same eight solid colors fullscreen, which is the standard way to spot a stuck (always-on) or dead (always-off) subpixel. The Contrast Test pairs the two extremes with four intermediate gray levels to gauge shadow detail and a Lorem Ipsum readability block for text legibility.