Gradient Banding Test
A gradient should fade smoothly from one shade to the next. On a screen with banding, it breaks into visible steps instead. This test fills your screen with gray and color gradients, so you can see where the steps appear.
Nine full-screen colors. Click, tap or press an arrow key to move to the next one.
How do I test for color banding?
Banding is easiest to see in a dim room on a large, smooth area. Work through these steps.
- Turn off night light, blue light filters and any eco or dynamic contrast mode.
- Start the test and look along each gradient from one end to the other.
- Note where smooth shading turns into visible steps, and whether the steps are tinted.
- Change one setting at a time, from the list below, and run the test again.
How much banding is normal?
Web pages use 8-bit color, which has 256 shades from black to white. Across a wide screen, each shade has to fill a strip several pixels wide.
Those strips are usually too close in shade to see. Near black, the eye is more sensitive to small changes, so faint even steps on the dark gradient are common on good screens.
What causes color banding?
Where the steps appear tells you a lot about the cause. Use this table as a starting point.
How do I reduce banding?
Start with the signal. In your graphics settings, choose full RGB range and RGB color format, and pick 10-bit color if your screen and cable support it.
Then check the screen. Reset the picture mode, turn off dynamic contrast and sharpening, and test again after each change. If a calibration profile adds tinted steps, try the screen's own color modes instead.
If heavy banding remains on the bright gradients with every setting reset, the panel itself may be at fault. Report it within the return window, with a photo of the gradient on screen.
What is dithering, and does it hide banding?
Dithering mixes nearby shades in a fine pattern, so the eye sees a shade in between. Many panels use it to show more shades than they really have. A 6-bit panel has 64 shades per color, or 262,144 colors in all, and dithering lets it pass for 8-bit.
Done well, dithering smooths gradients and you never notice it. On some screens you may see a faint shimmer or fine grain on dark gradients up close. That is dithering at work, not a fault.
How do I check a TV for banding?
Open this page in the TV’s browser or from a connected laptop, and look at the dark gradients from your seat. Then try a dark film scene with sky or smoke. Some TVs, including many LG and Sony models, have a Smooth Gradation setting that softens steps in videos.
Why test red, green and blue separately?
Each color is a separate channel with its own 256 shades. A fault in one channel can hide in a gray gradient but stand out on its own. That is why the test fades black into each color in turn.
Questions
Is a little banding normal?
Faint, evenly spaced steps on the dark gradient show on many good screens. Uneven, tinted or wide steps across the bright gradients point to a setting or a fault.
Does a 10-bit monitor remove banding?
It can reduce it, but only when the computer, cable and app all send 10-bit color. Most web pages, including this one, are drawn with 8-bit color.
Why does a video show banding when this test does not?
Video compression throws away fine shading, which leaves steps in skies and dark scenes. That banding is in the file, so a better screen cannot remove it.