Preview how your colors appear to users with color vision deficiency and check WCAG contrast ratios for accessibility compliance.
Understanding Color Blindness
Color blindness (color vision deficiency) occurs when one or more types of cone cells in the eye are absent or malfunction. It affects approximately 8% of men and 0.5% of women worldwide.
Types of Color Blindness - Protanopia: Missing L-cones (red receptors). Reds appear dark or black. Red/orange/green confusion. - Deuteranopia: Missing M-cones (green receptors). Most common type (~5β8% of males). Red/green confusion. - Tritanopia: Missing S-cones (blue receptors). Rare. Blue/yellow and purple/red confusion.
WCAG Contrast Requirements - AA: 4.5:1 for normal text, 3:1 for large text (18pt+) - AAA: 7:1 for normal text, 4.5:1 for large text
Design tip: never use color alone to convey information β always pair it with icons, patterns, or text labels.
Frequently Asked Questions
Color blindness (color vision deficiency) is a genetic condition where one or more types of cone cells β the photoreceptors responsible for color vision β are absent or function abnormally. Most people with color blindness are not completely color-blind but have difficulty distinguishing specific colors, particularly red and green.
Protanopia involves missing L-cones (long-wavelength, red-sensitive receptors), making reds appear very dark or invisible. Deuteranopia involves missing M-cones (medium-wavelength, green-sensitive receptors). Both types cause red-green confusion, but in protanopia reds appear darker while in deuteranopia the brightness is more similar. Deuteranopia is significantly more common.
WCAG 2.1 (Web Content Accessibility Guidelines) defines contrast requirements for digital content. Level AA requires a contrast ratio of at least 4.5:1 for normal text and 3:1 for large text (18pt or 14pt bold). Level AAA requires 7:1 for normal text and 4.5:1 for large text. These are the standards used by accessibility auditors globally.
Color blindness affects approximately 300 million people worldwide β about 8% of men and 0.5% of women. Deuteranopia/deuteranomaly (green-type) is the most common form, followed by protanopia/protanomaly (red-type). Tritanopia (blue-type) is rare and often acquired rather than inherited.
Blue and orange is one of the safest combinations for all types of color blindness. Avoid red and green combinations, which cause confusion for people with the most common forms of color vision deficiency. Also consider using dark blue vs. light yellow, or adding patterns, textures, or icons alongside color to convey information.
1) Use a color blindness simulator (like this tool) to preview designs. 2) Ensure WCAG AA contrast ratio (4.5:1+) for all text. 3) Never rely on color alone to convey meaning β always pair with icons, labels, or patterns. 4) Use browser extensions like Colorblindly or Stark during design reviews. 5) Test with real users with color vision deficiency when possible.
Inherited color blindness currently has no cure. Specially tinted glasses (like EnChroma) can enhance color distinction for some people, though effectiveness varies. Gene therapy research is ongoing. Acquired color blindness β from disease, medication, or injury β may improve if the underlying cause is treated.
This tool currently accepts hex color codes in #RRGGBB format. To convert RGB to hex, use the formula: hex = R in base-16 + G in base-16 + B in base-16. For example, rgb(59, 130, 246) = #3B82F6. You can also use any online RGB-to-hex converter tool.