Ketchup Later
#a91c1c
A red that is saturated. It is mid — the hardest range to put text on, either colour struggles.
Hex
#a91c1c
RGB
169, 28, 28
OKLCh
47.5% 0.176 27.2°
CIELAB (D50)
37.4, 55.3, 39.5
What is true of this colour, and of no other
- 9 other named colours sit within ΔE00 2 of it.
- It uses 91% of the chroma sRGB can show at this lightness and hue — close enough to the boundary that a wider display would show it slightly more vividly.
- As text on white it measures APCA Lc 83.7; on black, Lc -18.3. The sign is the polarity, which the WCAG ratio discards.
- Built into an eleven-step scale, 10 of the 10 adjacent pairs stay ΔE00 2 apart — see the ramp.
- protanopia and deuteranopia and tritanopia shift it by ΔE00 34.8 and 39.8 and 44.0 — no red cone.
Text on this colour
White text
7.32:1 — passes AA
Black text
2.87:1 — fails AA
White text is the better of the two at7.32:1. That is enough for body text.
The same colour, with one cone missing
As you see it
#a91c1c
protanopia
#42421e · ΔE00 34.8
deuteranopia
#63630a · ΔE00 39.8
tritanopia
#7c7c00 · ΔE00 44.0
The twelve nearest named colours
Ranked by CIEDE2000 — perceptual distance, not hex arithmetic. The closest isBloody Ruby at ΔE00 0.382: below 1.0 — an ordinary observer cannot tell these apart, even side by side. What the numbers mean.
- Bloody RubyΔE00 0.382 · #a81c1d
- Red MenaceΔE00 1.025 · #aa2121
- Blood RushΔE00 1.227 · #aa2222
- Tomato SunriseΔE00 1.723 · #aa251b
- Fresh AuburnΔE00 1.815 · #a52a24
- Boy RedΔE00 1.878 · #b3111d
- Siren ScarletΔE00 1.878 · #b21d1d
- Mammary RedΔE00 1.894 · #b00b1e
- Scarlet BlazeΔE00 1.956 · #b21f1f
- ChorizoΔE00 2.052 · #aa0011
- Büchel CherryΔE00 2.06 · #aa1111
- CarnelianΔE00 2.089 · #b31b1b
5 of these have no page of their own: pages exist for the 4,961 colours the dataset marks as good names.