Spotlight 36: 

Sizing

(WCAG 1.4.3, 2.5.5 & 2.5.8)

Let's talk about the requirements for sizing content.


Text sizing

While WCAG doesn't explicitly define a minimum size of text, it’s important that text is readable for most users. To support individuals with visual impairments, WCAG provides criteria for enlarging content and accessing information via screen readers. We explore enlarging requirements in Spotlight 33: Adaptivity.


Additionally, in terms of accessibility and contrast, according to WCAG 1.4.3 Contrast  (Minimum) (AA), any text smaller than 18 points (24 pixels) - or in the case of bolded text, smaller than 14 points (18.56 pixels) - is considered standard text and therefore higher contrast ratios apply. You can learn more about it in Spotlight 15: Contrast. Here's a visual recap: 

Contrast (WCAG 1.4.3 & 1.4.6) standard text size: min. 4.5:1 or min. 7:1 "larger text (18 points or 24 pixels and above) (14 points or 18.56 pixels and above - if bolded): min. 3:1 or min. 4.5:1
Sizing related to contrast (WCAG 1.4.3 & 1.4.6)

Sizing Related to Contrast Image Transcript

Contrast (WCAG 1.4.3 & 1.4.6)

The table shows that the AA compliance for standard text size is minimum 4.5 to 1, while the AAA compliance is minimum 7 to 1. 

The AA compliance for larger texts (18 points or 24 pixels and above, or 14 points or 18.56 pixels and above - if bolded) is minimum 3 to 1, while for AAA compliance, it’s 4. 5 to 1. 

The image ends with the LCA Spotlight logo. 

Interactivity 

WCAG also covers size requirements for interactive elements, such as buttons or icons.  WCAG 2.5.8 Target Size (Minimum) (AA) requires a target size of at least 24 by 24 CSS pixels for pointer inputs. The advanced version of this criterion, 2.5.5 Target Size - AAA (Enhanced), calls for a larger target size, setting the minimum at 44 by 44 CSS pixels (approximately 9 mm).


There are exceptions to these criteria. For instance, if the target size is unmodifiable by the author, if the content is in line with the text, or if the size is essential for conveying meaning, exemptions apply. Also, objects that are sufficiently spaced from one another may still meet the criterion as the spacing eliminates accidental activation.

Text and table-only image. The text reads: Target size (WCAG 2.5.5 & 2.5.8) The table shows that the target size for interactive elements (buttons, icons etc.) is 24 by 24 CSS pixels for AA compliance, and 44 by 44 CSS pixels for AAA compliance.
Target size (WCAG 2.5.5 & 2.5.8)

Line spacing

Finally, WCAG 1.4.8 Visual Presentation (Level AAA) combines a few recommendations. One of them states that line spacing is at least space-and-a-half within paragraphs, and paragraph spacing is at least 1.5 times larger than the line spacing.

The title reads: Line spacing (mentioned in WCAG 1.4.8). Underneath, an illustration shows that line spacing should be at least 1.5 and paragraph spacing should be at least 1.5 times larger than the line spacing.
Line spacing (mentioned in WCAG 1.4.8)

Resources:

Discussion questions:

Get Involved: Come to the LCA Spotlight LinkedIn group and join the conversation.

When you post in the community, use the hashtag #LCASpotlightSizing

Spotlight 35: Motion

Coming soon

Spotlight 37: TBC