What color contrast ratio is needed for WCAG AA?

WCAG AA requires a contrast ratio of at least 4.5:1 for normal text and 3:1 for large text (18pt or 14pt bold). Our checker shows both levels.

What is WCAG AAA contrast?

WCAG AAA is the highest accessibility standard, requiring 7:1 for normal text and 4.5:1 for large text. Meeting AAA ensures readability for users with moderate vision impairment.

How is contrast ratio calculated?

Contrast ratio is calculated using the relative luminance of the two colors: (L1 + 0.05) / (L2 + 0.05), where L1 is the lighter color. The ratio ranges from 1:1 (no contrast) to 21:1 (maximum contrast, black on white).

Color Contrast Checker

Check WCAG color contrast ratios for accessibility compliance. Test text and background color combinations.

Text Color

Background Color

Contrast Ratio

14.63 : 1

Normal Text

(below 18pt / 14pt bold)

AAA

Large Text

(18pt+ / 14pt+ bold)

AAA

Preview

The quick brown fox

jumps over the lazy dog. 0123456789

This text uses your selected color combination. Check if it's readable.

WCAG 2.1 Requirements

AA: 4.5:1 for normal text, 3:1 for large text
AAA: 7:1 for normal text, 4.5:1 for large text
Large text = 18pt (24px) or 14pt (18.5px) bold

Check Color Accessibility

Enter your text and background colors using hex codes or the color picker. The tool instantly calculates the WCAG contrast ratio and shows whether your combination passes AA and AAA standards for both normal and large text.

Why Color Contrast Matters

Poor color contrast makes text difficult or impossible to read for users with vision impairments, color blindness, or in bright sunlight. WCAG guidelines ensure your website is accessible to everyone. Many countries require WCAG AA compliance by law.

Frequently Asked Questions

What color contrast ratio is needed for WCAG AA?: WCAG AA requires a contrast ratio of at least 4.5:1 for normal text and 3:1 for large text (18pt or 14pt bold). Our checker shows both levels.
What is WCAG AAA contrast?: WCAG AAA is the highest accessibility standard, requiring 7:1 for normal text and 4.5:1 for large text. Meeting AAA ensures readability for users with moderate vision impairment.
How is contrast ratio calculated?: Contrast ratio is calculated using the relative luminance of the two colors: (L1 + 0.05) / (L2 + 0.05), where L1 is the lighter color. The ratio ranges from 1:1 (no contrast) to 21:1 (maximum contrast, black on white).