Color banding test

Gray and color gradients

You get four gradients: black to white, the darkest eighth of gray, a red, green and blue set, and a narrow band of sky blues. In the plain strip, every 8-bit level is a flat step. The dithered strip mixes the two nearest levels pixel by pixel, so from a normal distance you see the shade between them. RTINGS explains that many 8-bit panels do the same to show 10-bit signals, over time (FRC) or across neighboring pixels.

Start with the dark gradient: RTINGS says poor gradients lose detail in dark scenes with shadows, and in sunsets.

Banding or compression

Bands in a video or photo may be in the file. A 2025 study by Zheng and colleagues notes that compression still causes banding in smooth areas of high-definition video. Our gradients aren't compressed, so any bands here are 8-bit steps or come from your screen. The dithered strip tells you which. A faint shape that stays put across every gradient, such as an OLED taskbar, is image retention or burn-in, not banding.

Panel bit depth

By RTINGS's numbers, an 8-bit signal carries 256 levels per color, or 16.7 million colors. A 10-bit signal carries 1,024 levels, or 1.07 billion colors. FRC, the dithering over time, can flicker. RTINGS adds that when the flicker is visible at all, it shows in dark shades.

Graphics settings

Turn off color filters and auto brightness first: they change what a gradient shows. With HDR on, Windows can show SDR gradients too bright or washed out, Microsoft says.

How the color banding test works

The gradients are made at your screen's own pixel count, so nothing gets scaled. MDN's canvas reference says a canvas stores 8 bits per channel unless a page asks for more, so these gradients have 256 levels per color. They keep those 8-bit steps even over a 10-bit signal, so this test can't show whether your screen handles 10-bit content.

In a plain strip, each level gets a flat run of columns. In a dithered strip, each pixel gets the level just below or above the exact value. Fixed noise picks which, so that on average the pixels match the exact value. If your computer applies a color profile, it changes the values on their way to the screen, and a web page can't see that. You judge the result by eye.