Color Blindness Tester

This free color blindness tester bundles five screening tests in one place. TheIshihara plate test spans all three color-vision axes with selectable difficulty; the D-15 hue arrangement asks you to order color caps and scores the crossing pattern; theanomaloscope reproduces the classic Rayleigh red-green match; the Cambridge Landolt-C fades a colored gap toward the background to measure discrimination threshold; and theFarnsworth lantern mimics the signal-light test used for aviation and maritime roles.

Accuracy limits you should know: the result is display-dependent — brightness, contrast, dark mode, night-shift filters and ambient light all shift the colors, which is the single biggest limitation of any web plate test. The plates are procedurally generated, not the validated clinical Ishihara set. The protan-vs-deutan lean relies on an approximate luminosity model applied in sRGB without per-display calibration, so it reports a likely type (or "type undetermined"), not a determination. It cannot reliably separate full dichromacy from anomalous trichromacy, the mild / moderate / strong bands are ordinal screening buckets rather than clinical grades, and blue-yellow (tritan) detection is the weakest because it is hard to reproduce on sRGB. This is a screening aid to build intuition, not a diagnosis — see an eye-care professional for a proper assessment.