Oceanic Noir
#172b36
A blue that is nearly neutral — the hue shows only against a true grey. It is dark — it carries white text and needs care with black.
Hex
#172b36
RGB
23, 43, 54
OKLCh
27.7% 0.033 233.8°
CIELAB (D50)
16.2, -5.5, -9.8
What is true of this colour, and of no other
- No other named colour in the set is within ΔE00 2 of it — it stands alone.
- It uses 57% of the chroma sRGB can show at this lightness and hue.
- As text on white it measures APCA Lc 101.4; on black, Lc 0.0. 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 10.3 and 11.2 and 14.6 — no red cone.
Text on this colour
White text
14.63:1 — passes AA
Black text
1.44:1 — fails AA
White text is the better of the two at14.63:1. That is enough for body text.
The same colour, with one cone missing
As you see it
#172b36
protanopia
#292936 · ΔE00 10.3
deuteranopia
#262636 · ΔE00 11.2
tritanopia
#232352 · ΔE00 14.6
The twelve nearest named colours
Ranked by CIEDE2000 — perceptual distance, not hex arithmetic. The closest isTangaroa at ΔE00 2.296: between 2 and 5 — clearly two colours when compared, easily mistaken from memory. What the numbers mean.
- TangaroaΔE00 2.296 · #1e2f3c
- Elderberry BlackΔE00 2.494 · #1e323b
- Blue WhaleΔE00 3.081 · #1e3442
- Freinacht BlackΔE00 3.389 · #232f36
- Imperial PrimerΔE00 3.462 · #21303e
- Black BoxΔE00 3.497 · #0f282f
- Into the NightΔE00 3.524 · #1e3642
- Petrol SlumberΔE00 3.6 · #243640
- Blue-BlackΔE00 3.67 · #24313d
- Crow FeatherΔE00 3.733 · #102329
- NATO BlueΔE00 3.858 · #153043
- Black ChasmΔE00 4.022 · #102c33
8 of these have no page of their own: pages exist for the 4,961 colours the dataset marks as good names.