Porcini on Ms. Pac-Man Kiss
#d9ae86 on #ff00aa
Body text at this size
And the smaller size most interfaces actually use for paragraphs — the size that decides whether a pair is usable.
Caption text, which almost nothing passes.
WCAG 2.1
1.77:1
Fails AA
Not AAA (7:1). Swapping the two colours gives the same number — the ratio does not know which is the text.
APCA
Lc -21.3
Clears Lc 15 — disabled or purely decorative text, which is not meant to be read.
Light text on a darker ground — the negative sign is the polarity.
Colour difference
ΔE00 42.2
different colours
Above 10 — related only in the sense that both are colours.
What the text colour has to become
#331b00 is the nearest colour of the same hue that passes AA on #ff00aa, at 4.50:1. Only the lightness moved, and some chroma was given up to stay inside sRGB — which is the point: your colour stays recognisably your colour.
And to someone missing a cone
protanopia
Ratio 2.66:1, ΔE00 51.4.
deuteranopia
Ratio 1.53:1, ΔE00 30.8.
tritanopia
Ratio 1.12:1, ΔE00 2.8.
The weakest of the three is tritanopia, where the two are ΔE00 2.8 apart against 42.2 for a trichromat — effectively one colour. If anything on your interface depends on telling these apart, it needs a second signal.
Both colours have pages of their own: Porcini ·Ms. Pac-Man Kiss · the same pair the other way round ·all pairs