Dorn Yellow

#fff200

A yellow that is saturated. It is very light — it works as a page background, not as text.

Hex

#fff200

RGB

255, 242, 0

OKLCh

94.1% 0.200 105.7°

CIELAB (D50)

94.3, -9.8, 91.1

What is true of this colour, and of no other

22 other named colours sit within ΔE00 2 of it — this part of the space is crowded, and the names here are finer distinctions than most people make.
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 7.8; on black, Lc -96.5. 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.
All three dichromacies see it as very nearly the same colour you do: its hue is not the part carrying its identity.

Text on this colour

White text

1.17:1 — fails AA

Black text

17.95:1 — passes AA

Black text is the better of the two at17.95:1. That is enough for body text.

As text on white, it needs to change

#807900 is the nearest colour of the same hue that passes AA on white, at 4.50:1. Only the lightness moved, and some saturation was given up to stay inside sRGB.

Try it against your own background

The same colour, with one cone missing

As you see it

#fff200

protanopia

#f4f401 · ΔE00 2.8

deuteranopia

#f6f600 · ΔE00 2.8

tritanopia

#f9f900 · ΔE00 2.9

Run a whole palette through all three

The twelve nearest named colours

Ranked by CIEDE2000 — perceptual distance, not hex arithmetic. The closest isZheleznogorsk Yellow at ΔE00 0.224: below 1.0 — an ordinary observer cannot tell these apart, even side by side. What the numbers mean.

Zheleznogorsk YellowΔE00 0.224 · #fef200
MarsupilamiΔE00 0.447 · #fdf200
Yellow RoseΔE00 0.561 · #fff000
Flat YellowΔE00 0.57 · #fff005
Asfar YellowΔE00 0.644 · #fcef01
Hudson BeeΔE00 0.645 · #fdef02
TweetyΔE00 0.843 · #ffef00
AureolinΔE00 0.892 · #fdee00
Marsh MarigoldΔE00 0.96 · #ffef17
Níng Méng Huáng LemonΔE00 0.987 · #ffef19
Yellow SunshineΔE00 1.103 · #fff601
Cadmium YellowΔE00 1.103 · #fff600

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