Color Banding Test

Color banding is when a smooth gradient — a sky, fog, or shadow fade — displays as visible stripes or steps instead of a continuous blend. It happens when somewhere in the display chain there are not enough distinct shades to render the transition: a 6-bit panel (262,144 colors), an 8-bit bottleneck in cable or GPU settings, or aggressive picture processing that quantizes smooth tones. Our tool shows six lossless gradients so you can see exactly which colors and brightness ranges are affected.

Testing takes about two minutes: (1) Set normal brightness and disable "vivid" modes. (2) Click "Start Test" above and open the Gray Gradient. (3) View from your normal seating distance — smooth means healthy, stripes mean banding. (4) Repeat with red, green, blue, dark, and light gradients. (5) Toggle horizontal/vertical direction. (6) If you see stripes, work through the fixes: GPU color depth to max, better cable, full RGB range, updated drivers — then re-test on this same page.

Even true 8-bit panels (16.7 million colors) can band when the chain around them is weaker: a 6-bit+FRC panel advertised loosely, a GPU outputting 6-bit or limited-range color, an old HDMI 1.4 cable choking 4K bandwidth, or "noise reduction" processing that flattens subtle tones. Content matters too — heavily compressed streaming video bands on every display. The diagnostic value of this page is isolation: because our gradients are lossless, banding here rules out video encoding and points at your panel, cable, or GPU settings.

Yes. Insufficient cable bandwidth forces the GPU and display to negotiate down — often silently dropping to lower color depth or chroma subsampling (4:2:2 instead of 4:4:4), both of which cause banding. For 4K at 60Hz you need HDMI 2.0+ or DisplayPort 1.2+; for 4K at 120Hz you need HDMI 2.1 or DP 1.4. If banding appeared after a cable swap or a new GPU, the cable is suspect number one — and it is the cheapest thing to test. Re-run the gray gradient after swapping cables to compare directly.

Bit depth sets how many shades each red, green, and blue channel can show: 6-bit gives 64 shades per channel (262,144 total colors), 8-bit gives 256 per channel (16.7 million colors), and 10-bit gives 1,024 per channel (1.07 billion colors). The signature difference: 6-bit panels show bold, evenly-spaced stripes on smooth gradients; 8-bit panels look smooth except possibly in extreme dark tones; 10-bit panels are essentially band-free when fed a 10-bit signal. Many "8-bit" budget monitors are actually 6-bit+FRC (dithering simulated) — this test helps expose that.

Human vision is most sensitive to steps in dark tones, and dark gradients concentrate the few available near-black shades over large screen areas — so every weakness in bit depth shows up first in shadows, fog, and night skies. Additionally, some panels and "black stabilizer" gaming features crush or quantize near-black detail. That is why this tool includes a dedicated dark-range gradient (#000→#333): it is a torture test for exactly the tones where banding hides. Faint stepping only in the bottom 5% is normal on consumer panels.

Usually not. Streaming services compress video aggressively, and gradients are the first casualty — blocky, shifting patches in dark scenes are bitrate artifacts, not panel defects. The decisive test: pause the video and open this page. If our lossless gradients are smooth but YouTube bands, your monitor is innocent and the video encoding is guilty. Try a higher quality setting or a local high-bitrate file to confirm before touching any display settings.

Dithering (and temporal FRC — frame rate control) masks banding by sprinkling noise among adjacent shades so the eye averages them into intermediate tones. It works well: most 6-bit+FRC panels look convincingly smooth in normal content. But it is camouflage, not extra real shades — a torture gradient like our dark-range ramp can still reveal the underlying steps, and poor dithering can add faint grain visible nose-to-screen. Enable GPU dithering or "deep color" output if offered; it strictly helps.

Yes. Modern OLED phones typically render superb gradients — open this page in the mobile browser and check the gray and dark ramps. On TVs, use the built-in browser or cast from a laptop, and first disable "vivid", noise reduction, and energy-saving modes, which all quantize gradients. Also check whether the TV is receiving full-range RGB: many TVs default to limited range on HDMI, which is a classic hidden cause of banding that costs nothing to fix.

Completely safe. The tool displays calm static gradients rendered by normal CSS — no strobing, no high-brightness flashing, no hours-long pixel-fixer loops. There is nothing here that can damage LCD, OLED, or any other panel type, and a two-minute manual check is far below any burn-in threshold. All rendering is local with zero network requests, no camera access, and no data collection.

HDR usually reduces banding, because the standard 10-bit HDR pipeline carries four times as many shades as 8-bit SDR, and smoother ramps mean fewer visible steps. That is exactly why a gradient which looks striped in SDR can look clean the moment HDR is enabled. The catch is that HDR also raises peak brightness and stretches the tonal range, so any weak link in the chain becomes more visible: an 8-bit source, a subsampled signal, or a panel that accepts a 10-bit input and dithers it down internally will still show steps, now spread across a wider range. Test the same dark ramp in both SDR and HDR on your display and compare where the bands fall.

The operating system rarely states it plainly, so check the graphics driver instead. On Windows, open the GPU control panel and look for the output color depth or color format entry for your display; on Linux the display settings or the driver tool usually lists it. A 10-bit desktop mode needs all four links to agree: a 10-bit capable GPU output, a cable with enough bandwidth, a display input that accepts it, and a picture mode that does not force 8-bit. Once that is set, run a smooth gray ramp and compare it with the same ramp in 8-bit mode. If the band count is identical, the extra depth is not reaching the panel.