Color contrast
Also known as: Contrast ratio
Color contrast is the difference in brightness between text and its background. WCAG asks for at least 4.5:1 for normal text so people with low vision can read it.
In plain terms
Light-grey text on a white background might look elegant, but a lot of people simply can't read it — including anyone with ageing eyes or in bright sunlight. The fix is measurable: run the colours through a contrast checker and aim for 4.5:1 (or 3:1 for large text and for buttons, icons and borders).
Why it matters
Low contrast is the single most common accessibility failure on the web. It's easy to catch and easy to fix, and fixing it helps every user, not just those with a diagnosed impairment.
#767676 grey text on white passes at 4.54:1. The trendy #AAAAAA fails at 2.32:1 — readable to the designer, invisible to many users.
Related terms
Want your website checked against every WCAG requirement, not just the jargon? We run IAAP-certified audits with plain-English reports.
Request an Audit