Verify color combinations against WCAG accessibility standards
Ensure your website meets international accessibility standards. Audit color contrast ratios for WCAG 2.1 AA and AAA compliance to improve readability and user experience.
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The tool converts your HEX or RGB inputs into relative luminance values—a measure of perceived brightness. It then compares the lighter value against the darker value to produce a ratio ranging from 1:1 (no contrast, e.g., white on white) to 21:1 (maximum contrast, e.g., black on white). It instantly cross-references this ratio against the strict W3C Pass/Fail thresholds.
:root {
/* Passes WCAG AAA (7.0:1) on white backgrounds */
--color-primary-text: #1E2D47;
/* Use #F0F6FF for dark mode text */
}
.alert {
background-color: #FEE2E2;
color: #991B1B; /* 6.1:1 ratio */
}To pass WCAG AA compliance—which is the standard legal requirement in many regions—normal text must have a contrast ratio of at least 4.5:1. Large text (usually defined as 18pt regular or 14pt bold) requires a slightly lower ratio of at least 3.0:1.
WCAG AAA is the highest and strictest level of accessibility compliance. It requires a contrast ratio of 7.0:1 for normal text and 4.5:1 for large text. Achieving AAA is difficult and usually required only for specialized accessibility websites or specific government portals.
Yes. Under WCAG 2.1 guidelines, non-text elements (like icons, input borders, and charts) must also maintain a minimum contrast ratio of 3.0:1 against adjacent colors to ensure they are discernible.
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