Acoustic Brown on Abyssal Waters
#766b69 on #005765
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
1.60:1
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 -10.9
Below Lc 15: the draft treats this as not text.
Light text on a darker ground — the negative sign is the polarity.
Colour difference
ΔE00 32.8
different colours
Above 10 — related only in the sense that both are colours.
What the text colour has to become
#c9bdbb is the nearest colour of the same hue that passes AA on #005765, 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 1.45:1, ΔE00 14.8.
deuteranopia
Ratio 1.69:1, ΔE00 21.2.
tritanopia
Ratio 1.64:1, ΔE00 55.6.
The weakest of the three is protanopia, where the two are ΔE00 14.8 apart against 32.8 for a trichromat — still clearly two colours.
Both colours have pages of their own: Acoustic Brown ·Abyssal Waters · the same pair the other way round ·all pairs