Farnsworth D15 Test
Arrange these 15 screen colors from red to violet. Select two swatches to swap them, then submit to see this exercise’s order-error score. This page cannot predict whether you will pass any medical examination; it describes only this arrangement.
No account or sign-in is needed. Your arrangement is scored in this page.
BEFORE YOU START
Quick display self-check
The grayscale and color steps below are a visual preflight inspired by monitor test patterns; they are not a calibration or accuracy certification. EIZO documents grayscale and color gradation patterns, while Microsoft explains that display settings and color profiles affect display output.
Answer all three checks to get a quick screen-check conclusion before submitting a score.
This self-check uses your observations and has no sensor that measures the display. A failed check cannot identify whether the screen, its settings, room light, or visual perception caused the difference.
Put the colors in order
Select one swatch, then another to swap.Each color has a letter label, such as “Swatch A,” so you can identify and operate it without using color as its control label. The letter does not reveal the correct hue order.
Keyboard: Tab to a labeled swatch and press Enter or Space to select it; Tab to another swatch and press Enter or Space to swap. Press Escape to clear a selection. Tab to “Show my result” or “Shuffle and start again” and press Enter or Space. W3C requires keyboard operation and a visible focus indicator.
YOUR EXERCISE RESULT
Order-error score
0 reversed pairs out of 105
This score compares your row with this page’s generated hue sequence. It does not identify a color-vision type or grade a deficiency.
Screen colors and room lighting can change the colors you see.
This browser exercise is not a diagnosis or a clinical Farnsworth D-15 examination.
For an assessment, contact an eye-care professional or qualified testing service.
How to use this result
People in color-vision communities report: “There is no way to "prepare" for a colour blind test. That is like asking if you can prepare for a hearing test. Either your physiology can detect the colours (resp. sounds) or they can't.” That view does not predict your result here.
Use it to: compare this arrangement with this page’s generated hue sequence; the score counts reversed pairs in the row.
Do not use it to: identify or grade a color-vision type, compare yourself with a clinical norm, or certify that a display is calibrated.
For a more controlled assessment: use the physical D-15 procedure under the illumination specified in its instructions and ask an eye-care professional or qualified testing service to interpret it. 2021 Gulden D-15 instructions.
People in color-vision communities report: “The cost is close to $500 and it's not covered by insurance.” Treat it as one report, not your provider’s quote.
How this screen exercise is scored
The page generates 15 HSL screen colors at evenly spaced hue steps and shuffles their display order. The expected order is the generated red-to-violet sequence. No color-percentage, diagnosis, or type estimate is calculated.
Order error = Σ [rank(left) > rank(right)] for every pair of positions left < right
Each reversed pair adds one error. There are 15 × 14 ÷ 2 = 105 possible pairs, so the score ranges from 0 to 105; fewer reversed pairs means a closer match to this exercise’s sequence. This is a page-specific ordering score, not the crossover count used to read a physical D-15 test.
The two-tap swap and reversed-pair count give you a reproducible explanation for this exact row: the result reports how many color pairs appear in the opposite order from the page’s own generated sequence. A lower value describes this arrangement only; it cannot be translated into an eye condition.
People in color-vision communities report: “I got deutan result in the last version. Twice. And I am protan for most online and actual physical tests.” This screen cannot settle a physical-test result.
D-15 names and paper versus screen versions
“D15 color test” and “D15 colour test” are the US and UK spellings of the same color arrangement test: you order 15 generated screen swatches, and this page reports reversed pairs. The physical “Farnsworth D 15” is the Farnsworth dichotomous test described in the 2021 Gulden paper-cap instructions; this page uses generated screen colors instead of caps. If a police or railway application names a “Farnsworth D15 colour vision test” or simply a “Farnsworth test,” confirm which physical procedure the employer requires; this page’s score describes only its generated screen row.
- Pass
- The cap sequence is numerical and the circular plot has no crossovers.
- Mild failure
- Crossovers stay around the circle, usually near one or two cap positions.
- Major errors
- Crossovers go across the circle and often define a deficiency axis.
Those are the instructions’ descriptions of a physical test result. They are not score bands for this screen exercise, and this page does not assign any of them to you.
The physical procedure specifies controlled viewing conditions. This browser exercise uses generated display colors, so its order-error score cannot replace the physical cap test or professional assessment.