Untamed Red

#dd0022

A red that is about as vivid as sRGB can show at this lightness. It is mid — the hardest range to put text on, either colour struggles.

Hex

#dd0022

RGB

221, 0, 34

OKLCh

56.5% 0.229 25.4°

CIELAB (D50)

47.2, 72.8, 49.7

What is true of this colour, and of no other

  • 8 other named colours sit within ΔE00 2 of it.
  • It sits exactly on the sRGB boundary: at this lightness and hue the gamut has nothing left, and a wider display would show a more colourful version of it.
  • As text on white it measures APCA Lc 72.4; on black, Lc -29.3. 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 41.0 and 47.1 and 51.9 — no red cone.

Text on this colour

White text

5.13:1 — passes AA

Black text

4.10:1 — large text only

White text is the better of the two at5.13:1. That is enough for body text.

The same colour, with one cone missing

As you see it

#dd0022

protanopia

#515125 · ΔE00 41.0

deuteranopia

#7f7f00 · ΔE00 47.1

tritanopia

#a1a100 · ΔE00 51.9

Run a whole palette through all three

The twelve nearest named colours

Ranked by CIEDE2000 — perceptual distance, not hex arithmetic. The closest isPiercing Red at ΔE00 0.796: below 1.0 — an ordinary observer cannot tell these apart, even side by side. What the numbers mean.

8 of these have no page of their own: pages exist for the 4,961 colours the dataset marks as good names.