WCAG Contrast Ratio Calculator
Free online wcag contrast ratio calculator that runs entirely in your browser.
How the WCAG Contrast Ratio Calculator works
The WCAG Contrast Ratio Calculator works on Text color (hex), Background color (hex) and shows the result as you type. The same input always gives the same answer — refresh the page and you will see exactly the same figure.
Formula used
WCAG Contrast Ratio Calculator is computed by the formula below, using the inputs you provide.
Inputs used: Text color (hex), Background color (hex).
Worked example
Take the default example — text color (hex) of #111111, background color (hex) of #ffffff:
- ratio: 18.88
Frequently asked questions
- Is the WCAG Contrast Ratio Calculator free?
- Yes. There is no signup, no usage limit and no watermark — the checker runs entirely in your browser.
- Does the WCAG Contrast Ratio Calculator store or send my data?
- No. Every calculation happens locally in the page, so the numbers you type are never uploaded or logged.
- Does it work on a phone and offline?
- Yes — the page is a single lightweight file that adapts to any screen size. Once it has loaded it keeps working without a network connection.
- What inputs does the WCAG Contrast Ratio Calculator need?
- Text color (hex), Background color (hex). Change any of them and the result updates instantly.