Gradient banding test: where steps in a smooth ramp come from

How this is calculated

Every color travels a long path before it reaches your eyes: the page, the browser's color management, the operating system's color profile, the graphics driver, the cable signal, the monitor's processing and finally the panel. Any of those steps can throw away levels and create bands. An 8-bit signal has 256 levels per channel, so a ramp across a wide screen spreads each level over many pixels, and a faint stepped look can appear even when everything is working. Look at the gray ramp first, in both directions, which you can switch in the setup. Then look at the color ramps. If only one channel bands, or if the gray ramp has pink or green tints, a color profile or calibration curve is a likely cause. The gray steps help you check for merged levels: two neighboring patches that look identical. To narrow down the cause, change one thing at a time. Turn off night light or blue light filters. Set your graphics driver to full range RGB for a PC monitor and the highest bit depth it offers. Disable dynamic contrast and other picture enhancers in the monitor menu. Try a different browser. If the banding changes when you change a software setting, the panel isn't the cause.

Verdict

Mild banding in the darkest part of the ramp is common and rarely shows in photos or games. If banding is strong, look for the setting that changes it, starting with color profiles, night light and driver range. If nothing changes it and the same bands show in real content like sky photos or smoke in games, the monitor's processing or panel is the likely source.