Black Box on Ms. Pac-Man Kiss
#0f282f 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
4.27:1
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 39.5
Clears Lc 30 — the floor: below this the draft considers text not readable at any size.
Dark text on a lighter ground.
Colour difference
ΔE00 46.1
different colours
Above 10 — related only in the sense that both are colours.
What the text colour has to become
#0a242b is the nearest colour of the same hue that passes AA on #ff00aa, 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 2.62:1, ΔE00 27.4.
deuteranopia
Ratio 5.19:1, ΔE00 40.5.
tritanopia
Ratio 7.49:1, ΔE00 78.7.
The weakest of the three is protanopia, where the two are ΔE00 27.4 apart against 46.1 for a trichromat — still clearly two colours.
Both colours have pages of their own: Black Box ·Ms. Pac-Man Kiss · the same pair the other way round ·all pairs