A11ying with Sanna - Web Content Accessibility Guidelines a guide to the accessibility requirements
2 Operable

2.4.13 Focus Appearance

Conformance level: AAA
Criterion released in WCAG version: 2.2

Official description of the success criterion

When the keyboard focus indicator is visible, an area of the focus indicator meets all the following:

  • is at least as large as the area of a 2 CSS pixel thick perimeter of the unfocused component or sub-component, and
  • has a contrast ratio of at least 3:1 between the same pixels in the focused and unfocused states.

Exceptions:

  • The focus indicator is determined by the user agent and cannot be adjusted by the author, or
  • The focus indicator and the indicator's background color are not modified by the author.
     

What to do?

Use a focus indicator of sufficient size and contrast.

Why is it important?

Many people can't see small changes in visual appearance, including older people.

More about this criterion elsewhere