Protanopia/Protanomaly — Red cone deficiency. Affects ~1% of males. Reds appear darker, confused with greens and browns.
Deuteranopia/Deuteranomaly — Green cone deficiency. Most common, affects ~5% of males. Greens and reds appear similar.
Tritanopia/Tritanomaly — Blue cone deficiency. Very rare (~0.01%). Blues and yellows are affected.
Achromatopsia — Total color blindness. Extremely rare. Vision is entirely in grayscale.
Blue Cone Monochromacy — Only blue cones function. Very rare inherited condition.

This simulator uses the Machado et al. (2009) color matrix method, which operates in linear RGB space to approximate dichromatic and anomalous trichromatic vision. While highly representative, actual color perception varies between individuals. The severity slider allows you to adjust the intensity for anomalous types. For critical accessibility decisions, always combine with manual WCAG contrast checks and user testing.

Upload screenshots of your UI or use the built-in UI demonstration to see how buttons, alerts, charts, and form elements appear. Key practices: (1) Avoid red-green combinations for critical distinctions. (2) Add icons or text labels alongside color indicators. (3) Use patterns or textures in charts. (4) Ensure sufficient contrast ratios (4.5:1 minimum). (5) Test with multiple color blindness types — deuteranopia is most common.

No. All image processing happens entirely in your browser using JavaScript Canvas API. Your images are never uploaded, transmitted, or stored on any server. This tool is fully client-side and privacy-friendly. You can use it offline after the page loads.

-opia (dichromacy) means one cone type is completely missing. The person has only two functioning cone types.
-anomaly (anomalous trichromacy) means all three cone types are present, but one type has shifted spectral sensitivity, causing reduced discrimination. Use the severity slider to simulate varying degrees of anomalous color vision.