The 24-Pixel Tap Target Minimum and Why It Is a Floor
The Web Content Accessibility Guidelines (WCAG) 2.2, at level AA, set a minimum tap target size of 24 by 24 CSS pixels in success criterion 2.5.8 (W3C WAI, 2023). Meeting it is the compliance floor, but 24 pixels is the smallest acceptable size, not a good size for buttons people use most.
What the guidance says
The 24-pixel rule has five exceptions (W3C WAI, 2023):
- Spacing: a smaller target passes if a 24-pixel circle centered on it does not overlap neighboring targets.
- Equivalent: another control that does the same thing meets the size.
- Inline: the target is a link within a sentence of text.
- User agent: the size is the browser’s default and not changed by the site.
- Essential: the specific size or placement is essential.
The stricter AAA criterion, 2.5.5, sets 44 by 44 CSS pixels and is recommended for important controls (W3C WAI, 2023).
What it means for a business website
Small tap targets are common on small business sites: social media icons in the footer, close buttons on popups, arrows on image sliders, tightly stacked menu links. Each one is a small target to hit with a finger.
The 24-pixel floor gives you a clear compliance check for these secondary controls. Your main actions, the buttons that lead to a call, booking, or purchase, deserve the 44-pixel size.
What to do
- Audit every icon, arrow, and close button on your mobile pages against the 24 by 24 pixel minimum.
- Where a small icon cannot grow, add spacing around it so it meets the spacing exception.
- Size primary buttons at 44 pixels or more instead of stopping at the minimum.
Sources
- Understanding SC 2.5.8 Target Size (Minimum). W3C Web Accessibility Initiative, 2023.
- Understanding SC 2.5.5 Target Size (Enhanced). W3C Web Accessibility Initiative, 2023.