Contrast Checker
Verify that text is easily readable on any background color according to international readability standards.
Sample Main Heading
This paragraph demonstrates how body text renders with the selected color pairing. Good contrast prevents visual fatigue and ensures all users can read clearly across any screen.
Accessible color contrast checker (WCAG 2.1 AA & AAA ratios)
Light gray text on white backgrounds or low-contrast action buttons do not just hurt users with visual impairments—they make reading difficult for anyone using a phone under bright sunlight. International accessibility standards (WCAG) require minimum contrast ratios to guarantee readability.
With this tool, you can test the exact contrast ratio between any background and text color. Instantly see whether your pairing passes AA and AAA standards for normal and large text, and use smart adjustment suggestions to tweak brightness automatically if it falls short.
Before and after comparison
Check the difference in file size, visual quality, and speed.
2.1:1 Ratio
Hard to read in sunlight and fails WCAG guidelines
- •Fails accessibility audits and compliance standards.
- •Difficult to read on mobile screens and outdoors.
- •Increases bounce rates and form abandonment.
7.8:1 Ratio
Crisp readability across all lighting conditions
- ✓Easily clears AA (4.5:1) and AAA (7:1) requirements.
- ✓Comfortable reading for everyone on desktop and mobile.
- ✓One-click intelligent color suggestion to fix failing ratios.
When you will need to check color contrast
Website & mobile app accessibility audits
Ensure buttons, headings, and paragraph text comply with WCAG 2.1 international readability guidelines.
Forms, inputs & error alerts
Verify that error alerts, disabled button states, and form placeholders remain distinctly visible.
Design systems & brand style guides
Define official brand color pairings with guaranteed legibility across digital applications.
Frequently asked questions about WCAG contrast
For standard text (under 18 pt or 14 pt bold), the minimum required ratio is 4.5:1. For large text or bold headlines, the minimum is 3:1.
Level AA is the recognized legal standard for websites and businesses worldwide. Level AAA is the stricter standard (minimum 7:1) recommended for maximum readability.
If a color pairing fails the required ratio, the algorithm calculates the minimum luminance adjustment needed to pass without altering the original hue.