There is no list of ADA approved fonts and no list of ADA compliant colors, which is the first thing to know because plenty of pages sell both. What the standard sets is measurable: a contrast ratio between text and its background, text that can be resized to 200% without loss of content, and no information carried by colour alone. This page is what those rules mean for a palette and a type scale, and how to check yours in an afternoon.
What the contrast rule actually requires
WCAG's contrast minimum asks for a ratio of at least 4.5:1 for normal text and 3:1 for large text, and a separate criterion asks 3:1 for the visual boundaries of interactive components. That is the whole colour rule for text. Check the palette including its states: disabled greys, placeholder text and the brand colour on white are the three that usually fail, and each of them fails on every page at once.
What makes a typeface work, since no font is certified
Distinguishable letterforms (an I, an l and a 1 that differ), generous x-height, real weights rather than synthesised bold, and enough letter spacing at small sizes. Beyond that, size and line height do more for readability than the typeface does: 16 pixels minimum for body text, 1.5 line height, and a measure that does not run past about 80 characters.
Colour alone is the rule people miss
A required field marked only in red, an error border, a chart with six series distinguished only by hue, a link that is only a colour change: all four fail. Each needs a second signal, whether text, an icon, an underline or a pattern. It is the cheapest rule to follow at design time and one of the most annoying to retrofit.
Questions people ask about ada accessible fonts
Is there an ADA font list?
No. Any page selling one is selling a claim the standard does not make.
Does dark mode change the ratios?
The requirement is identical; the palette usually has to be rechecked because the failing pairs differ.
What about images of text?
Avoid them: they cannot be resized or recoloured, and the criterion asks that text be real text wherever possible.