Summer Crush on Flash in the Pan
#f2d6da on #ff9977
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
1.53:1
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 -22.9
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 21.8
different colours
Above 10 — related only in the sense that both are colours.
What the text colour has to become
#574144 is the nearest colour of the same hue that passes AA on #ff9977, at 4.50:1. Only the lightness moved — which is the point: your colour stays recognisably your colour.
And to someone missing a cone
protanopia
Ratio 1.74:1, ΔE00 21.7.
deuteranopia
Ratio 1.44:1, ΔE00 20.8.
tritanopia
Ratio 1.18:1, ΔE00 4.2.
The weakest of the three is tritanopia, where the two are ΔE00 4.2 apart against 21.8 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: Summer Crush ·Flash in the Pan · the same pair the other way round ·all pairs