Color Contrast Checker: How to ensure accessible text on the web

Color contrast is essential for readability and accessibility. This guide explains how contrast is calculated and how to use our tool to validate color pairings on your site.

What is color contrast and why it matters

Text must be readable against its background for all users, including those with vision differences. WCAG defines contrast ratios to quantify readability. Higher ratios usually mean easier reading, especially for body text on websites.

How the checker works

The checker takes two colors, computes their relative luminance, and reports the contrast ratio. It also indicates whether the pairing passes the WCAG AA and AAA thresholds for normal and large text.

How to use the tool

Pick the foreground and background colors using the color pickers or enter hex values. The tool updates the ratio live and shows a preview with the chosen colors.

Practical examples

For example, black text on white background yields a high ratio, while pale text on a light background may fail. Use the tool to test several pairings and choose accessible options.

Tips for improving contrast

• Increase the difference between foreground and background lightness.
• Darken the text color or lighten the background color if needed.
• Avoid relying solely on color to convey information; use text or icons as well.

Conclusion

Ensuring adequate color contrast improves readability and accessibility. Use the color contrast checker during design and development to validate color pairings before launch.