Master Chief on Hint of Blue
#507d2a on #cee1f2
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
3.64:1
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 54.5
Clears Lc 45 — large or heavy display text.
Dark text on a lighter ground.
Colour difference
ΔE00 46.0
different colours
Above 10 — related only in the sense that both are colours.
What the text colour has to become
#426e19 is the nearest colour of the same hue that passes AA on #cee1f2, 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 3.49:1, ΔE00 44.9.
deuteranopia
Ratio 3.73:1, ΔE00 46.5.
tritanopia
Ratio 3.58:1, ΔE00 33.1.
The weakest of the three is tritanopia, where the two are ΔE00 33.1 apart against 46.0 for a trichromat — still clearly two colours.
Both colours have pages of their own: Master Chief ·Hint of Blue · the same pair the other way round ·all pairs