The contrast ratio requirements in the Web Content Accessibility Guidelines (WCAG) are directly related to the conformance levels A, AA, and AAA, which indicate the extent to which web content meets accessibility standards. Here’s how contrast ratio requirements differ across these levels:

WCAG Contrast Ratio and Conformance Levels

• Level AA (Intermediate Level):

Normal Text: A minimum contrast ratio of 4.5:1 is required for regular-sized text (typically up to 18pt or 24px).

Large Text: A minimum contrast ratio of 3:1 is required for large text (18pt or 24px and larger).

• Level AAA (Highest Level):

Normal Text: A minimum contrast ratio of 7:1 is required for regular-sized text.

Large Text: A minimum contrast ratio of 4.5:1 is required for large text.

Summary of Contrast Ratio Requirements:

Key Points:

• Level AA focuses on ensuring that the content is accessible to a wider range of people with visual impairments, balancing accessibility with design flexibility.

• Level AAA aims for the highest level of accessibility, making content as readable as possible for people with significant visual impairments, though this level is not always required due to its stringent standards.

By meeting these contrast ratio requirements, web content becomes more accessible and readable, providing a better user experience for individuals with visual impairments.