Colour Arrangement Test
Order 15 colour caps by hue, Farnsworth D-15 style. See how smoothly you arrange the colour circle and whether errors line up with a red-green or blue-yellow confusion axis.
What it measures
This is an at-home, screen-based version of a colour-arrangement task in the spirit of the Farnsworth D-15 panel. It checks how well you can tell similar colours apart and place them in smooth hue order. Rather than asking you to read a hidden number, it asks you to arrange a ring of equally bright colour caps in sequence — the same idea eye-care professionals use to sort people into normal colour vision versus a likely confusion axis (red-green or blue-yellow). It cannot diagnose; it is a friendly indication of whether your colour discrimination looks typical on this screen.
How it works
You see one fixed reference cap and 15 movable caps, all the same lightness and saturation so that only hue changes. The caps are shuffled, and you place them one at a time, each time picking the colour that looks like the smallest next step from the last cap. When all 15 are placed, the tool compares your order to the ideal walk around the hue circle. It sums the hue distance between neighbouring caps (your total error), counts how many times you jumped right across the circle instead of to the nearest colour (crossings), and looks at where those large jumps fall to estimate a likely confusion axis. Few or no crossings suggests typical colour discrimination; clustered large jumps near the red, green, or blue-yellow region suggest a possible deficiency along that axis.
Tips for an accurate result
- 1Trust your first impression — Pick the cap that most naturally continues the colour flow. Overthinking small steps tends to add errors rather than remove them.
- 2Use the undo button — If a placement feels wrong as soon as you see it next to its neighbour, undo and try the alternative — that is exactly how the clinical panel is meant to be re-checked.
- 3Re-test on a different screen — Because screens vary, repeating the test on another device and getting the same pattern is far more meaningful than a single run.
- 4Note your real-world clues — Difficulty with traffic signals, coloured wiring, ripe fruit, or map colours is useful context to mention to an optometrist alongside this result.