Leave a clear basis for color matching text and background.
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Color Contrast CheckerUser Guide
Enter the opaque text color and background color, calculate the contrast using the sRGB relative brightness formula of WCAG 2.2, and check the AA/AAA general text and large character thresholds.
How to use
Enter #RGB or #RRGGBB text and background colors, or use the color selection controls.
Press Check Comparison to check the four thresholds for judging unrounded values.
View a color preview, swap colors if necessary, and export a comparison report.
Formats and limits
Only opaque sRGB solid colors are accepted; transparency, gradients, or image backgrounds are not supported.
AA general text 4.5:1/large characters 3:1; AAA general text 7:1/large characters 4.5:1. Large type should be at least 24 CSS px, or about 18.67 CSS px bold.
Output
TXT report with color code, contrast, four judgments, and W3C source.
Frequently asked questions
Does a passing value mean that the website is accessible?
Doesn't mean. Only opaque solid text contrast is checked here; focus, keyboard, structure, subtitles, and other accessibility requirements must still be verified separately.
The file name and content are only processed in your browser and are not transmitted to the server. The original file will not be overwritten. Please export the required results before leaving the tool.