The Ishihara test is a widely recognized pseudoisochromatic plate assessment designed to detect red-green color vision deficiencies, including protanopia (reduced red sensitivity) and deuteranopia (reduced green sensitivity).

This interactive in-browser tool presents four standardized screening plates composed of multicolored dots forming hidden numerals: Plate 1 (demonstration plate displaying "12", visible to all vision types), followed by Plates 2, 3, and 4 (displaying "8", "29", and "5" under normal trichromatic vision, which individuals with red-green deficiencies typically perceive as "3", "70", or "2").

For example, viewing Plate 1 presents a numeral 12 for validation. Entering 12, 8, 29, and 5 through each successive plate records a complete 4-plate sequence and displays your answers alongside standard target responses.

Disclaimer: This tool is intended for informal screening purposes only. Screen calibration, display brightness, and ambient lighting can alter color rendition. A conclusive clinical diagnosis requires an in-person examination by an optometrist or ophthalmologist using calibrated physical plates.

All screening inputs and plate answers are evaluated locally in your browser. No vision responses or personal data are stored or sent to remote servers.