How does the Color Memory Test work?
A color fills the screen for 3 seconds, then a blank for 1. Then you rebuild it with three sliders: hue (which color it is), lightness, and colorfulness (from grey to as vivid as your screen can show). Each slider's track shows the colors it would give, so you can see where you are going. After each color, yours appears beside the real one with how many points off it was. There are 5 colors, one from each part of the color wheel.
What do the points mean?
Points measure how different your color is from the real one: 0 is identical, and the higher the number, the further off. One point is a hundredth of the distance between the two colors in OKLab, a color space designed by Björn Ottosson in 2020 so that equal distances look about equally different. Color scientists call a number like this a ΔE (delta E). It is the same measure as on the Color Difference page, worked out on the colors exactly as your screen was sent them.
As a guide, the CSS Color 4 standard treats a difference of 0.02 in OKLab, 2 points here, as the smallest a person is likely to notice. A result near 2 means your copy would be hard to tell from the original side by side; most memories are further off than that.
What do lightness, colorfulness and hue tell you?
Your result is your average difference over the 5 colors. Beside it, the same differences are split into the three things you set, which says which way your memory drifts:
- Lightness: on average, did you remember the colors lighter or darker than they were?
- Colorfulness: did you make them more vivid or more muted?
- Hue: how far round the color wheel you were, in degrees, whichever way.
A steady drift one way, say every color remembered a little more vivid, is a habit of your memory rather than bad luck, and it shows up again if you play twice.
How are the colors chosen?
Each game spaces its 5 colors round the hue circle, so you never get five blues. Their lightness is between 50% and 85% on OKLab's scale, and their colorfulness between 45% and 90% of the most vivid your screen can show at that hue and lightness. That keeps every color inside what a standard screen can display, and away from greys, where hue barely matters.
Your screen's settings change how every color looks, but they change the original and your copy in the same way, so the comparison stays fair. To remember a color, name it as exactly as you can (“dusty pink, quite light”) and check its lightness against the page around it. For memory of positions and patterns, try Visual Memory.