Plate 1 of 9
What number do you see?
Your results plate by plate
This screening is not a medical diagnosis. See an eye care professional for a clinical evaluation.
What Color Is This?
A color identification app built for how you actually see.
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About this screening
This is a 9-plate pseudoisochromatic screening that tests for red-green and blue-yellow color vision deficiency. It uses two established clinical methodologies:
Ishihara-style plates (6 plates) present numbers hidden in fields of colored dots. The foreground and background colors sit on opposite sides of the red-green or blue-yellow confusion axis, with matched luminance so hue is the only available cue. Individuals with color vision deficiency cannot distinguish the figure from the background.
HRR-style plates (3 plates) use geometric shapes instead of numbers, which avoids digit-recognition bias and allows testing participants who cannot read numerals. The Hardy-Rand-Rittler test is the standard clinical complement to Ishihara for identifying both the type and severity of deficiency.
Plate 1 is a control: it uses luminance contrast rather than chromatic contrast, so it should be visible regardless of color vision type. If the control plate is missed, the result is flagged as inconclusive (likely a screen brightness or lighting issue).
Limitations: This is a screen-based approximation. Clinical Ishihara and HRR tests use precisely calibrated printed pigments under standardized illumination (CIE Illuminant C). Display color rendering varies by device, panel type, brightness, and ambient lighting. This screening can indicate the likely presence and type of color vision deficiency, but it cannot replace a clinical evaluation.
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