Guide
How to Check a New Monitor Before the Return Window Closes
Dead pixels, backlight bleed and IPS glow are three different things with three different verdicts. Here is…
Colour Bit Depth Test
The same grey ramp quantised to 6, 8 and 10 bits, so you can tell a true 8-bit panel from a 6-bit panel with dithering.
Screen Tests
Nothing uploaded
No sign-up
Free, unlimited
The test starts automatically — follow the prompts above.
In short
Bit depth is how many distinct levels the panel can display per colour channel, and the practical question is whether your 8-bit monitor is genuinely 8-bit or a 6-bit panel using frame rate control to fake it. This shows the same grey ramp quantised to 6, 8 and 10 bits so you can compare them directly. On a true 8-bit panel, the 6-bit strip shows obvious steps while the 8-bit and 10-bit strips look smooth and nearly identical. If the 8-bit strip bands almost as badly as the 6-bit one, the panel is 6-bit with dithering — which is extremely common in laptops and budget monitors and is not a fault, just a specification that was described optimistically. What your browser reports is no help here: browsers report 24-bit colour almost universally regardless of the real panel, which is exactly why this test uses your eyes instead. Before concluding anything, check the graphics driver is sending full RGB range rather than limited, since a limited-range signal produces banding that looks identical to a low bit depth.
How to use the Colour Bit Depth Test
- The test starts on its own — no button to press and nothing to install.
- Follow the prompt in the test panel and watch the readings update live.
- Press Reset to start over with a clean slate.
About the Colour Bit Depth Test
The Colour Bit Depth Test the same grey ramp quantised to 6, 8 and 10 bits, so you can tell a true 8-bit panel from a 6-bit panel with dithering. It runs as plain JavaScript inside the page, which means there is no upload step, no queue and no size limit imposed by a server — the only limit is your own device.
What people use it for
- Checking whether a monitor advertised as 8-bit really is.
- Deciding whether 10-bit output is worth enabling.
- Diagnosing banding in photos and gradients.
Press Fullscreen above before judging anything. A colour patch surrounded by page furniture tells you very little — the panel needs to be filling the whole screen, ideally in a dark room, with any night-light or blue-light filter switched off.
Explained in our guides
All guidesFrequently asked questions
How do I read the result?
On a true 8-bit panel the 6-bit strip shows obvious steps while the 8-bit and 10-bit strips look smooth and nearly identical. If the 8-bit strip bands visibly too, the panel is almost certainly 6-bit with frame rate control.
My browser says 24-bit colour. Does that prove anything?
No. Browsers report 24-bit almost universally regardless of the real panel, which is why this test uses your eyes rather than that value.
Does the Colour Bit Depth Test cost anything?
No charge and no sign-up. There is no free tier to run out of because there is no paid tier — inputtesthub.com is funded by advertising rather than by metering the page.
Does anything I enter leave my computer?
No. The Colour Bit Depth Test runs entirely in your browser using JavaScript. Your input never reaches inputtesthub.com or any third party — open your browser's Network tab while you use it and you will see no request go out.
What do people use the Colour Bit Depth Test for most?
In practice it gets used for three things: checking whether a monitor advertised as 8-bit really is. Deciding whether 10-bit output is worth enabling. Diagnosing banding in photos and gradients. It is built for exactly those cases rather than being a general-purpose tool with this bolted on.
Is there anything to watch out for?
Press Fullscreen above before judging anything. A colour patch surrounded by page furniture tells you very little — the panel needs to be filling the whole screen, ideally in a dark room, with any night-light or blue-light filter switched off.
Does the Colour Bit Depth Test need an app or a driver?
No installation, no extension and no driver. The Colour Bit Depth Test uses the browser's own device APIs and begins as soon as the page loads, so there is nothing to press first. Press Reset at any point to start over with a clean slate.
Related screen tests tools
All 3801
White Screen
Fills your entire screen with solid white. Cleaning the screen, spotting dust and dark…
02
Black Screen
Fills your entire screen with solid black. Finding stuck pixels, backlight bleed and IPS glow…
03
Red Screen
Fills your entire screen with solid red. Checking the red sub-pixels across the panel and…
04
Green Screen
Fills your entire screen with solid green. Checking green sub-pixels — the channel the eye is…
05
Blue Screen
Fills your entire screen with solid blue. Checking blue sub-pixels and spotting the colour…
06
Cyan Screen
Fills your entire screen with solid cyan. Testing green and blue together, which often exposes…
07
Magenta Screen
Fills your entire screen with solid magenta. Testing red and blue together and checking for…
08
Yellow Screen
Fills your entire screen with solid yellow. Testing red and green together — the brightest…
09
Grey Screen
Fills your entire screen with solid grey. The best single colour for judging panel uniformity…
10
Orange Screen
Fills your entire screen with solid orange. A warm mid-tone that shows tint shifts across the…