Blue Moon

#3992a8

A cyan that is muted. It is light — black text sits on it comfortably, white text does not.

Hex

#3992a8

RGB

57, 146, 168

OKLCh

61.6% 0.089 217.1°

CIELAB (D50)

56.0, -22.1, -19.9

What is true of this colour, and of no other

  • 2 other named colours sit within ΔE00 2 of it.
  • It uses 81% of the chroma sRGB can show at this lightness and hue.
  • As text on white it measures APCA Lc 63.2; on black, Lc -38.5. 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.
  • protanopia and deuteranopia and tritanopia shift it by ΔE00 22.9 and 22.5 and 23.7 — no red cone.

Text on this colour

White text

3.59:1 — large text only

Black text

5.85:1 — passes AA

Black text is the better of the two at5.85:1. That is enough for body text.

As text on white, it needs to change

#248197 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

#3992a8

protanopia

#8b8ba8 · ΔE00 22.9

deuteranopia

#8080a9 · ΔE00 22.5

tritanopia

#7171ff · ΔE00 23.7

Run a whole palette through all three

The twelve nearest named colours

Ranked by CIEDE2000 — perceptual distance, not hex arithmetic. The closest isWinter Time at ΔE00 1.43: between 1 and 2 — a trained eye spots it when the two touch; nobody spots it across a room. What the numbers mean.

  • Winter TimeΔE00 1.43 · #4090a2
  • Enchanted WellΔE00 1.766 · #3994af
  • ScooterΔE00 2.282 · #308ea0
  • Aqua DanceΔE00 2.327 · #3896a7
  • Alpine LakeΔE00 2.368 · #4598ab
  • Cape PondΔE00 2.505 · #0092ad
  • Kelp’thar Forest BlueΔE00 2.572 · #0092ae
  • PelorusΔE00 2.628 · #2599b2
  • Tropical LagoonΔE00 2.697 · #1e98ae
  • ZeftronΔE00 2.837 · #0090ad
  • Aegean SeaΔE00 2.87 · #508fa2
  • Rainy MoodΔE00 2.921 · #4499aa

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