Grey Screen — Fullscreen Neutral Grey for Uniformity & Banding Tests

A fullscreen neutral grey for checking screen uniformity, banding and backlight bleed, or as a calm neutral background. Free, local, adjustable shade.

What it does

This page shows a mid-grey (#808080) screen fullscreen. A flat grey is one of the best ways to spot uneven brightness, color tint, vignetting or backlight clouding on a display, and it works as a neutral backdrop when you’re judging colors on screen.

How it works

Grey has equal red, green and blue values, so any visible color cast is the panel’s, not the image’s. Raise or lower the shade by dragging up or down, or step through grey values with the ↑ and ↓ arrow keys; the screen stays neutral because only lightness changes. (Dragging sideways changes hue, so keep your drags vertical.) Note that #808080 is a mid-grey code value, not a calibrated reflectance card: a photographer’s 18% grey card is a different thing. For the same grey in other formats, the color format converter handles rgb and hsl.

How to use it

1. Press Go fullscreen in a dim room.
2. Look for brighter or darker patches, colored tints in the corners, and visible stepping.
3. Try lighter and darker greys with ↑ and ↓ to see how the panel behaves at different levels.
4. Press Esc to exit.

FAQ

What does backlight bleed look like on grey?

Lighter patches or glow along the edges and corners, most visible on darker greys in a dim room. Test it on the black screen as well.

Does a grey screen calibrate my monitor?

No. It helps you spot problems, but proper calibration needs a hardware colorimeter and software.

Is grey or gray correct?

Both are accepted. You can type either into the color box.

Privacy

Everything runs in your browser. Nothing is uploaded and no network requests are made while you use it.