How colour contrast works
Large text means at least 18pt (about 24px), or 14pt (about 18.66px) bold. Normal text is anything smaller. WCAG 2.1 Level AA requires 4.5:1 for normal text and 3:1 for large text; Level AAA raises that to 7:1 and 4.5:1. User-interface elements (like form borders and icons) and meaningful graphics need at least 3:1.
A passing ratio doesn't guarantee a fully accessible design, but failing contrast is one of the most common — and most easily fixed — accessibility barriers. If a colour is part of your brand, A11ytek verifies contrast and recommends adjustments, but we leave final colour decisions to you. See our AODA compliance checklist for the bigger picture.