Calculate contrast ratio between foreground and background colors with AA/AAA pass-fail checks for accessible UI text.
Last updated: February 23, 2026
Calculate contrast ratio between foreground and background colors with AA/AAA pass-fail checks for accessible UI text. This tool runs in-browser for fast results without account setup.
Yes. WCAG Contrast Checker is free to use on ConvertCrunch.
Results depend on the inputs and assumptions you provide. Always validate final numbers or outputs against your official workflow before publishing or filing.
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Contrast Preview Text
Quick brown fox jumps over the lazy dog.
Contrast ratio: 14.63:1
AA (normal): Pass | AAA (normal): Pass