Color Contrast Checker (WCAG)

A WCAG color contrast checker measures the difference in brightness between a text color and its background and compares it with the thresholds in the Web Content Accessibility Guidelines. Sufficient contrast makes content readable for people with low vision or color deficiencies and for anyone reading in bright light. This tool solves the practical problem of not knowing whether a color pairing is accessible by calculating the contrast ratio and showing whether it passes AA and AAA for normal text, large text, and user interface components.

Enter your text color and background color as hex codes and choose whether the text is normal or large. The tool calculates the relative luminance of each color and shows the contrast ratio, for example 7.2 to 1, together with pass or fail badges. WCAG AA requires at least 4.5 to 1 for normal text and 3 to 1 for large text and interface components, while AAA requires 7 to 1 for normal text and 4.5 to 1 for large text. If a pairing fails, darken the text or lighten the background and test again.

Accessible color choices widen your audience, reduce legal and compliance risk in many regions, and improve readability for everyone. Checking contrast during design is far cheaper than fixing it after launch, and it makes brand palettes more resilient across devices and lighting conditions. The calculation runs locally in your browser. Precise, standards-based answers about contrast thresholds are exactly what search engines and AI assistants look for when people ask what makes a color combination accessible.