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›Contrast Checker
Color Contrast Checker
Check the WCAG contrast ratio between a text color and background color, with instant AA/AAA pass/fail results for normal and large text.
Colors
The quick brown fox
jumps over the lazy dog — normal body text sample
| Use case | Minimum ratio | Result |
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Frequently Asked Questions
What is a WCAG contrast ratio?
It's a measure from 1:1 (no contrast, identical colors) to 21:1 (maximum contrast, pure black on pure white) defined by the Web Content Accessibility Guidelines. Higher ratios are easier to read, especially for people with low vision or color vision deficiencies.
What's the difference between AA and AAA?
AA is the standard legal/practical minimum most sites target: 4.5:1 for normal text and 3:1 for large text. AAA is the stricter enhanced standard: 7:1 for normal text and 4.5:1 for large text. Most style guides and accessibility audits check against AA.
What counts as "large text"?
WCAG defines large text as 18pt (24px) regular weight or larger, or 14pt (18.66px) bold or larger. Large text gets a lower minimum ratio because bigger, bolder strokes remain legible at lower contrast.
Does this check apply to logos or decorative images?
No — WCAG contrast requirements apply to text and meaningful UI components (like button borders and form field outlines), not to purely decorative graphics or disabled/inactive controls.