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Focus appearance explained

First posted in Accessibility; updated 22nd September 2022

There’s some great stuff coming up in version 2.2 of the Web Content Accessibility Guidelines (WCAG), but there’s one rule that’s particularly difficult to understand: 2.4.11 Focus Appearance.

I cover it in my over-simplified explanation of WCAG 2.2, but this is one where it’s worth going into more detail.

What the rule applies to

The rule applies to ‘user interface components’, which means:

  • form fields
  • links
  • buttons

Essentially, any element you typically interact with.

Note: this can also include things like horizontally-scrolling tables.

Indicator style

There are two ways to indicate focus:

  1. An outline
  2. A shape

I’m going to run with the outline approach as that’s the one most designers are likely to use.

The focus outline should:

  • be at least 1px
  • be a solid line
  • go round the whole element

Colour contrast

The colour of the focus indicator is important too, so that it stands out nicely. The contrast ratio must be at least:

  • 3:1 against the unfocused state of the element
  • 3:1 against the background it sits on
  • 3:1 against the element (e.g. a button) that has focus

There’s a wee bit of flexibility here, but I’d keep it simple and use those three rules. If you really want to know, the contrast ratio can be less than 3:1 against the element that has focus, and the element in its unfocused state, but the indicator must be at least 2px thick.

An example would be a button, where the indicator might be the same colour as the button (1:1), but if the button grows by 2px along all four edges, that’s allowed. There still has to be enough contrast against the background, though: you need to be able to see that the element is bigger!


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Here are a couple more posts for you to enjoy. If that’s not enough, have a look at the full list.

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    Every idea comes from a good place, but some well-intended features are actually bad for usability; limiting form field input is one of those things.

  2. Getting VoiceOver to shut up

    The whole point of VoiceOver is that it talks out loud, but sometimes you need it to be quiet for a moment.