#2B4173
Closest named color: Twilight Blue (#0A437A). oklch(38.4% 0.09 264.6), rgb(43, 65, 115).
Aa
White text reads best on this color (9.96:1).
About this color
#2B4173 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.090 and its hue 265°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.028 away. White text reads best on it, at 9.96:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.090) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.10:1 |
| White text | 9.96:1 |
Values
| HEX | #2B4173 |
| RGB | rgb(43, 65, 115) |
| HSL | hsl(222, 46%, 31%) |
| OKLCH | oklch(38.4% 0.09 264.6) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #2B4173 | 9.96:1 | AAA | Lc -97.1 | Preferred for body text |
| Black text on #2B4173 | 2.10:1 | Fails | Lc 11.0 | Not readable |
| #2B4173 text on white | 9.96:1 | AAA | Lc 93.0 | Preferred for body text |
| #2B4173 text on black | 2.10:1 | Fails | Lc -9.5 | Not readable |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 900.
-
Step 50
50
#F2F5FC
oklch(97% 0.01 267.4)
-
Step 100
100
#E3EAF7
oklch(93.6% 0.019 263)
-
Step 200
200
#CDD9F3
oklch(88.4% 0.038 265.8)
-
Step 300
300
#ABC1ED
oklch(80.9% 0.067 264.1)
-
Step 400
400
#7F9FE4
oklch(70.6% 0.108 264.7)
-
Step 500
500
#5F86DC
oklch(63.1% 0.137 264.4)
-
Step 600
600
#466ECA
oklch(55.6% 0.15 264.4)
-
Step 700
700
#385BAF
oklch(49.1% 0.14 264.7)
-
Step 800
800
#2F4B8D
oklch(42.7% 0.114 264.7)
-
Step 900
900 (this color)
#2B4173
oklch(38.4% 0.09 264.6)
-
Step 950
950
#182542
oklch(26.9% 0.057 264.6)
#2B4173 with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #2B4675 | 0.015 |
| Deuteranopia (no green cones) | #213F72 | 0.014 |
| Tritanopia (no blue cones) | #004C54 | 0.078 |
| Achromatopsia (no color) | #434343 | 0.090 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2B4173
#2B4173
oklch(38.4% 0.09 264.6)
- #573F00
#573F00
oklch(38.4% 0.079 84.1)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #2B4173, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.028
- Dark Grey Blue #29465B ΔE 0.048
- Light Navy #155084 ΔE 0.048
- Cobalt #1E488F ΔE 0.048
- Marine Blue #01386A ΔE 0.050
- Deep Sea Blue #015482 ΔE 0.059
- Dark Slate Blue #483D8B ΔE 0.061
- Prussian Blue #1D3557 ΔE 0.061
Use #2B4173 in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.