Protanopia Simulator
View your colors through protanopia (red-blind color blindness). Affecting 2% of males, protanopia makes reds appear dark and causes red-green confusion. Test red buttons, error messages, and brand colors to ensure they remain visible.
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RGB(16, 185, 129)
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Protanopia
Red-blind (~2% of males)
Protanopia affects about 2% of males and causes difficulty perceiving red light. Reds appear darker — sometimes almost black — and red-green distinctions are severely reduced. Red text on dark backgrounds can become nearly invisible to protanopic users. Always check red buttons and error messages for sufficient contrast under this simulation.
Protanopia
Red-blind (~2% of males)
Normal Vision
Trichromatic — all three cone types
Deuteranopia
Green-blind (~6% of males)
Tritanopia
Blue-blind (rare)
Achromatopsia
Total color blindness
Frequently Asked Questions
What is protanopia?
Protanopia is a type of red-green color blindness where the red-sensitive cone cells (L-cones) in the retina are missing. It affects approximately 2% of males. People with protanopia perceive reds as much darker — sometimes nearly black — and have significant difficulty distinguishing red from green and red from dark brown or black.
Why is protanopia especially important for web designers?
Red is widely used in web design for error states, destructive actions, warnings, and CTAs. Under protanopia, red text can appear nearly black — causing errors to blend with body text. Red buttons on dark backgrounds can become almost invisible. Always test red elements against their backgrounds with our simulator to ensure they remain distinguishable.
How does protanopia differ from deuteranopia?
Both are red-green color blindness types, but protanopia affects red perception (L-cones) while deuteranopia affects green perception (M-cones). The practical difference: protanopes see reds as much darker than deuteranopes do. A red button that looks dark brown to a deuteranope may look nearly black to a protanope.
What design precautions help protanopic users?
Avoid using red text for critical information on dark backgrounds — it may become invisible. Use high-contrast white or yellow text instead. Never rely on red alone to indicate errors; always pair with an icon (like a warning triangle) or a text label. Blue is perceived normally by protanopes, making blue-orange a good alternative palette.