In plain English
This AAA rule is a bundle of readability details for blocks of text. In plain terms: keep columns fairly narrow (around 80 characters), do not fully justify text (the ragged gaps hurt readers), use line spacing of at least 1.5, and let text grow to 200% without forcing sideways scrolling. It also asks that users be able to set their own text and background colours.
Most of this is just good typography. The user-choosable-colours part is the stricter piece that keeps it at AAA.
Who this is for
- People with dyslexia, who lose their place in wide, tightly-packed, justified text.
- Low-vision readers, who need reflow and comfortable spacing when enlarging.
How to check and fix it yourself
Check your body-text styling: left-aligned (not justified), line-height at least 1.5, and a readable max column width.
.article-body {
max-width: 70ch; /* keeps lines short and readable */
line-height: 1.6; /* at least 1.5 */
text-align: left; /* not justified */
}Then zoom the browser to 200% and confirm text reflows instead of scrolling sideways.
Where we can help
We review your long-form text (blog posts, policies, product descriptions) against these readability details and flag justified text, cramped spacing, or over-wide columns. Readable text also keeps visitors on the page, which helps the metrics that matter.