Color Contrast Checker

Check any text and background color pair against WCAG AA and AAA contrast standards, live as you pick colors.

Runs entirely in your browser, nothing is uploaded
Large heading text Regular body text sample to preview readability.
1.00Contrast ratio
AA normal text
AA large text
AAA normal text
How to use

Check contrast in three steps

  1. Pick or type a text color and a background color, hex input and color picker stay in sync.
  2. Watch the live preview update with your exact colors on real sample text.
  3. Check the ratio and pass or fail marks for AA and AAA at both normal and large text sizes.
Why use it

Why people use the Color Contrast Checker

Everything worth knowing before you dive in.

How it helps

Text that looks fine to one person can be unreadable to another, which is why the Web Content Accessibility Guidelines set a minimum contrast ratio between text and its background. This tool calculates that ratio the same way the specification does and checks it against every relevant threshold at once.

Built for real use

AA is the standard most sites aim for, requiring a ratio of at least 4.5 to 1 for normal text and 3 to 1 for large text such as headings. AAA is the stricter standard, useful for content aimed at users with low vision, requiring 7 to 1 for normal text. The live preview shows your exact colors on sample text so the numbers translate into something you can actually see.

Private by default

This matters beyond compliance, low contrast text is genuinely harder to read for a large share of visitors, including anyone using a phone screen outdoors in bright sunlight.

Pro tip

If a color combination fails at normal text size but passes at large text, consider bumping the font weight or size rather than changing the color entirely, since that alone can meet the large text threshold.

FAQ

Common questions

What contrast ratio do I need to pass WCAG AA?

At least 4.5 to 1 for normal text, or 3 to 1 for large text, which is defined as 18pt or larger, or 14pt and bold.

What counts as large text for these rules?

Text at 18 point or larger, or 14 point and bold, qualifies for the more lenient large text threshold.

Is AAA required by law?

Most accessibility regulations reference AA as the baseline. AAA is a stricter, optional standard for content that needs to be readable by as wide an audience as possible.