About the Color Contrast Checker Online Free Tool

The Color Contrast Checker Online Free Tool calculates the WCAG contrast ratio between foreground and background colors. It reports common AA and AAA pass/fail checks for normal and large text and updates a live preview block.

How to Use the Color Contrast Checker Online

1. Enter the foreground and background HEX colors.
2. Load the sample if you want a known passing contrast pair.
3. Run the contrast check.
4. Review the ratio and WCAG pass/fail results.

Choosing Options Correctly

Use final design colors from the actual UI state you are checking. Test hover, disabled, focus, dark mode, and small text states separately when they use different colors.

Common Use Cases

• Check text and background color pairs before release.
• Validate design token changes against WCAG targets.
• Compare normal text and large text accessibility thresholds.

Quick FAQ

Does this check font size automatically?
No. It reports ratio and WCAG thresholds; you decide whether the text qualifies as normal or large.

Can I enter shorthand HEX?
Use full HEX values such as #1b1b1b for reliable results.

What should I do if contrast fails?
Adjust the foreground or background color and retest until the target AA or AAA threshold passes.

Is this only for SEO?
No. Contrast is primarily an accessibility and usability check, which can also support better page quality.