Color Contrast Calculator
Check foreground/background color contrast ratio against WCAG 2.1 AA and AAA compliance levels.
How to Use the Color Contrast Calculator
- Enter foreground RGB values (0-255).
- Enter background RGB values (0-255).
- Click Calculate.
- Check WCAG AA and AAA pass/fail results.
Use Cases
- •WCAG accessibility compliance
- •UI color palette validation
- •Accessible design system creation
Formula
Ratio = (L1 + 0.05) / (L2 + 0.05) where L = relative luminance
Frequently Asked Questions
How accurate is this calculator?
Results are based on standard industry formulas and are suitable for preliminary estimates.
What units are used?
Standard IT units (requests/sec, ms, %, USD) are used unless otherwise noted.
Is it free?
Yes, all calculators are completely free.