Cover of Night on Ghost Writer
#494e4f on #bcb7ad
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
4.23:1
Large text only
Not AAA (7:1). Swapping the two colours gives the same number — the ratio does not know which is the text.
APCA
Lc 48.3
Clears Lc 45 — large or heavy display text.
Dark text on a lighter ground.
Colour difference
ΔE00 41.1
different colours
Above 10 — related only in the sense that both are colours.
What the text colour has to become
#454a4b is the nearest colour of the same hue that passes AA on #bcb7ad, 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 4.17:1, ΔE00 40.5.
deuteranopia
Ratio 4.26:1, ΔE00 41.3.
tritanopia
Ratio 4.25:1, ΔE00 46.5.
The weakest of the three is protanopia, where the two are ΔE00 40.5 apart against 41.1 for a trichromat — still clearly two colours.
Both colours have pages of their own: Cover of Night ·Ghost Writer · the same pair the other way round ·all pairs