Color Blindness Simulator

Color blindness (color vision deficiency) is the decreased ability to see color or differences between colors. It affects approximately 8% of men and 0.5% of women worldwide. Most cases are inherited and present from birth. The most common types are red-green color blindness (protanopia and deuteranopia), while blue-yellow color blindness (tritanopia) is very rare. Complete color blindness (achromatopsia) is extremely rare.

The main types are: Protanopia (red-blind, missing L-cones, ~1% of males), Deuteranopia (green-blind, missing M-cones, ~1% of males), Tritanopia (blue-blind, missing S-cones, very rare ~0.001%), Achromatopsia (total color blindness, extremely rare), Protanomaly (red-weak, reduced L-cone function, ~1% of males), and Deuteranomaly (green-weak, reduced M-cone function, most common at ~5% of males). Anomalies are less severe than anopias.

The simulator uses mathematical algorithms to transform RGB color values based on how different types of color blindness affect cone cells in the eye. It applies transformation matrices that simulate the missing or deficient cone types (L-cones for red, M-cones for green, S-cones for blue). Select a color using the color picker or quick test colors, and the tool instantly shows how that color appears to people with each type of color vision deficiency.

Designers should use color blindness simulators to ensure their designs are accessible to everyone. About 1 in 12 men have some form of color vision deficiency. By testing colors, you can: ensure critical information isn't conveyed by color alone, verify text remains readable, check that UI elements have sufficient contrast, avoid problematic color combinations (like red-green), and comply with WCAG accessibility guidelines. This makes your designs more inclusive and user-friendly.

Both are types of red-green color blindness but affect different cone cells: Protanopia is red-blind (missing L-cones that detect long wavelengths/red light), making reds appear darker and harder to distinguish from blacks, browns, and greens. Deuteranopia is green-blind (missing M-cones that detect medium wavelengths/green light), making greens harder to distinguish from reds, browns, and oranges. While similar, they produce slightly different color confusions.

Yes! This is an excellent tool for testing website accessibility. Test your brand colors, button colors, link colors, and text colors to ensure they work for color-blind users. The text readability preview helps verify text remains distinguishable. However, remember that color alone shouldn't convey information - always use additional indicators like icons, patterns, or text labels. Also test with our Contrast Checker tool to ensure WCAG contrast ratio compliance.

Common problematic combinations: Red and green (most common issue for protanopia/deuteranopia), light green and yellow, blue and purple (for tritanopia), light colors generally (all types), red and brown/black (protanopia), green and brown/orange (deuteranopia). Safe approaches: use high contrast, add patterns or textures, include text labels, use blue with orange instead of red with green, ensure lightness differences between colors, and test with this simulator before finalizing designs.

The simulator provides a close approximation based on scientific color transformation matrices, but individual experiences vary. Color vision deficiency exists on a spectrum - some people have mild deficiencies while others have severe. Environmental factors like lighting also affect color perception. This tool is best used as a design guide rather than an exact medical representation. For critical accessibility work, consider testing with actual color-blind users or using multiple simulation tools for comparison.