AA v/s AAA color contrast WCAG (Accessibility)?

When designing digital products, it is essential to ensure they are accessible to everyone, including people with visual impairments. The Web Content Accessibility Guidelines (WCAG) provides a set of standards to help designers achieve this. One critical aspect of these guidelines is color contrast.

WCAG specifies two levels of contrast: AA and AAA. The AA level requires a minimum contrast ratio of 4.5:1 for normal text and 3:1 for large text (at least 18pt or 14pt bold). The AAA level requires a higher contrast ratio of 7:1 for normal text and 4.5:1 for large text. While AA contrast is the minimum requirement for accessibility, designers should aim for AAA contrast when possible. The reason designers should aim for AAA contrast is that AAA contrast provides better readability for people with low vision, especially for those with age-related vision loss.

However, achieving AAA contrast can be challenging, mainly when working with branding colors or specific design requirements. In such cases, designers may compromise on differences to maintain consistency and branding.

When deciding on the appropriate level of contrast, designers should consider the purpose of the design and the target audience. For instance, if the design is for a website with a primarily elderly audience, then AAA contrast would be more appropriate.

In conclusion, designers should strive to meet the WCAG standards for color contrast to ensure accessibility for people with visual impairments. While AA contrast is the minimum requirement, AAA contrast is recommended when possible to provide better readability for people with low vision. However, designers should also consider the purpose of the design and the target audience when deciding on the appropriate level of contrast.

A quick summary distinguishes AA and AAA contrast per the WCAG standards.

Note that the contrast ratio is calculated by comparing the relative luminance of the foreground text color to the background color. Designers can use various online tools to check the contrast ratio of their designs and ensure compliance with the WCAG standards.