Color Blindness Checker Calculator
Color Contrast Checker
Check WCAG contrast ratio between foreground and background colors
Color Vision Simulation
See how a color appears to people with color vision deficiency
Formula
Contrast Ratio = (L1 + 0.05) / (L2 + 0.05) where L = relative luminance | L = 0.2126R + 0.7152G + 0.0722B
Frequently Asked Questions
What is WCAG contrast ratio and why does it matter?
WCAG (Web Content Accessibility Guidelines) defines minimum contrast ratios for text readability. Level AA requires 4.5:1 for normal text and 3:1 for large text. Level AAA requires 7:1 and 4.5:1 respectively. Meeting these standards ensures your content is readable for users with low vision.
How common is color blindness?
About 8% of males and 0.5% of females have some form of color vision deficiency. Deuteranopia (green-blind) is most common at about 5% of males. This means roughly 1 in 12 men cannot distinguish certain colors, making accessible design important.
How can I make my designs color-blind friendly?
Use high contrast ratios, do not rely on color alone to convey information, add patterns/textures/labels alongside color, test with simulation tools, and use color palettes designed for accessibility (like ColorBrewer).