Display Test (Monitor Test Patterns)
An all-in-one, full-screen display test for any monitor, laptop or TV. Step through six reference patterns to spot dead pixels, tint, backlight bleed, banding, sharpness and geometry faults in a single pass.
← → ← → change pattern · Esc to exit
What each pattern checks
Dead or stuck pixels, color tint and backlight uniformity on a single flat color.
Banding, black crush and white clipping across smooth and stepped gray ramps.
Color accuracy and saturation against reference bars and a hue sweep.
Scaling, focus and convergence using a one-pixel grid and checkerboard.
Edge cropping, centering and alignment against a full-screen grid with markers.
Shadow and highlight detail in near-black and near-white steps.
Backlight bleed and near-black detail only show up in low ambient light.
Run at the panel’s native resolution and 100% browser zoom for a 1:1 pixel map.
Wipe off dust and smudges so they are not mistaken for stuck pixels.
A display test fills the screen with extreme, uniform patterns so faults have nowhere to hide. This suite runs six of them — solid colors, a grayscale ramp, color bars, a sharpness grid, a geometry grid and near-black/near-white contrast steps — checking your panel’s color, backlight uniformity, gamma, sharpness and edge alignment in one sitting. Everything runs locally in your browser; nothing is uploaded.
What each pattern reveals
| Pattern | What it reveals | A healthy panel shows |
|---|---|---|
| Solid colors | Dead or stuck pixels, color tint, backlight uniformity | A flat, even field with no bright dots or cast — faint corner glow is normal LCD bleed |
| Grayscale ramp | Banding, black crush, white clipping | A smooth sweep with the darkest and lightest steps still distinct |
| Color bars | Saturation and color accuracy | Pure, saturated bars matching the reference hues |
| Sharpness grid | Scaling, focus, convergence | Fine, even texture — no blur or shimmering moiré |
| Geometry grid | Edge cropping and centering | Lines reaching cleanly into all four corners, image centered |
| Contrast steps | Shadow and highlight detail | Near-black and near-white steps that stay separate, not crushed or clipped |
For a fair read, dim the room — backlight bleed and near-black detail only show up in low ambient light. Set the display to its native resolution and keep the browser at 100% zoom so one image pixel maps to one screen pixel, then go full screen and let your eyes settle on each pattern before judging it. Clean the screen first so dust isn’t mistaken for stuck pixels, and view each pattern straight on — brightness and tint shift noticeably off-axis on VA and TN panels.
Run a display test whenever you buy or return a monitor, laptop or TV — checking a new panel inside the return window is the cheapest insurance against dead pixels and heavy backlight bleed. It’s also worth a pass after transporting or mounting a display, after a driver or cable change, or whenever color, sharpness or uniformity suddenly looks off. To drill into one fault, pair this suite with the focused Dead Pixel Test for locating individual bad pixels or the Screen Bleeding Test for grading backlight bleed.