Radical Red

#ff355e

A red that is about as vivid as sRGB can show at this lightness. It is light — black text sits on it comfortably, white text does not.

Hex

#ff355e

RGB

255, 53, 94

OKLCh

65.6% 0.233 16.1°

CIELAB (D50)

57.5, 75.3, 28.7

What is true of this colour, and of no other

  • 4 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 61.3; on black, Lc -40.4. 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 35.5 and 47.6 and 59.3 — no red cone.

Text on this colour

White text

3.55:1 — large text only

Black text

5.92:1 — passes AA

Black text is the better of the two at5.92:1. That is enough for body text.

As text on white, it needs to change

#e9124d is the nearest colour of the same hue that passes AA on white, at 4.50:1. Only the lightness moved.

Try it against your own background

The same colour, with one cone missing

As you see it

#ff355e

protanopia

#6a6a60 · ΔE00 35.5

deuteranopia

#999955 · ΔE00 47.6

tritanopia

#bdbd00 · ΔE00 59.3

Run a whole palette through all three

The twelve nearest named colours

Ranked by CIEDE2000 — perceptual distance, not hex arithmetic. The closest isNeon Fuchsia at ΔE00 1.358: between 1 and 2 — a trained eye spots it when the two touch; nobody spots it across a room. What the numbers mean.

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