Black Box on Diesel

#0f282f on #322c2b

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

1.12:1

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 0.0

Below Lc 15: the draft treats this as not text.

Too close to call.

Colour difference

ΔE00 16.8

different colours

Above 10 — related only in the sense that both are colours.

What the text colour has to become

#7d98a1 is the nearest colour of the same hue that passes AA on #322c2b, 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

Body text

Ratio 1.08:1, ΔE00 7.2.

deuteranopia

Body text

Ratio 1.14:1, ΔE00 10.6.

tritanopia

Body text

Ratio 1.13:1, ΔE00 38.6.

The weakest of the three is protanopia, where the two are ΔE00 7.2 apart against 16.8 for a trichromat — still two colours, but a closer call than it looks to you.

Both colours have pages of their own: Black Box ·Diesel · the same pair the other way round ·all pairs