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Color Contrast Checker
Calculate WCAG contrast ratios for two opaque sRGB colors and report text thresholds.
Your results will appear here.
Three steps. That’s it.
A useful toolkit for text, data, images and calculations.
- 01
Add your input
Choose a tool, enter values or select a file.
- 02
Make it yours
Adjust the options and run the action.
- 03
Take the result
Copy the result or download its file.
WCAG contrast ratio calculator online
Check text contrast between two opaque sRGB colors. The ratio alone does not certify full WCAG conformance or evaluate images and complex backgrounds.
How to use it
Enter Text color (#RGB or #RRGGBB) or select Try example. Review Background color. Select Run tool and inspect the result before copying or downloading.
Options and example settings
Worked examples
Check text contrast between two opaque sRGB colors.
Worked example — Color Contrast Checker
Settings: Background color: #ffffff
Input:
#333333
Output:
Contrast ratio: 12.63:1 AA normal text (4.5:1): PASS AA large text (3:1): PASS AAA normal text (7:1): PASS AAA large text (4.5:1): PASS
The example output has 5 lines. Compare its order, separators and whitespace with the input before copying the result.
Choose the right tool
The ratio compares two opaque sRGB colors. Actual readability also depends on text size, weight, surrounding colors and the rendered interface.
Limitations and common mistakes
- The ratio alone does not certify full WCAG conformance or evaluate images and complex backgrounds.
Frequently asked questions
How can I check colour contrast online?
Enter Text color (#RGB or #RRGGBB) or select Try example. Review Background color. Select Run tool and inspect the result before copying or downloading.
Where is my input processed?
The bundled tool processes input in your browser. It does not upload tool input to a conversion service. Other site plugins, analytics, advertising and browser extensions may have separate behavior.
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