#2B3371
Closest named color: Marine Blue (#01386A). oklch(35.1% 0.106 274.1), rgb(43, 51, 113).
Aa
White text reads best on this color (11.57:1).
About this color
#2B3371 is a dark, moderately saturated blue. In OKLCH its lightness is 35%, its chroma 0.106 and its hue 274°. Its hue sits on the cool side of the wheel. The nearest named color is Marine Blue (#01386A), ΔE 0.041 away. White text reads best on it, at 11.57:1.
| Hue family | Blues |
| Lightness | dark (35%) |
| Chroma | moderately saturated (0.106) |
| Temperature | cool |
| Nearest name | Marine Blue (#01386A) |
| Black text | 1.81:1 |
| White text | 11.57:1 |
Values
| HEX | #2B3371 |
| RGB | rgb(43, 51, 113) |
| HSL | hsl(233, 45%, 31%) |
| OKLCH | oklch(35.1% 0.106 274.1) |
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 #2B3371 | 11.57:1 | AAA | Lc -100.1 | Preferred for body text |
| Black text on #2B3371 | 1.81:1 | Fails | Lc 7.5 | Not readable |
| #2B3371 text on white | 11.57:1 | AAA | Lc 96.4 | Preferred for body text |
| #2B3371 text on black | 1.81:1 | Fails | Lc 0.0 | 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
#F3F5FD
oklch(97.1% 0.011 274.9)
-
Step 100
100
#E5E9FA
oklch(93.6% 0.023 275.4)
-
Step 200
200
#D0D8F7
oklch(88.6% 0.044 274)
-
Step 300
300
#B0BDF5
oklch(80.8% 0.081 274.3)
-
Step 400
400
#889AF0
oklch(70.8% 0.127 273.7)
-
Step 500
500
#6D7EEA
oklch(63.1% 0.162 274.1)
-
Step 600
600
#5664D9
oklch(55.6% 0.178 274)
-
Step 700
700
#4752BC
oklch(49% 0.165 274.1)
-
Step 800
800
#3A4498
oklch(42.7% 0.136 274)
-
Step 900
900 (this color)
#2B3371
oklch(35.1% 0.106 274.1)
-
Step 950
950
#1D2347
oklch(27.1% 0.067 274)
#2B3371 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) | #0F3C73 | 0.034 |
| Deuteranopia (no green cones) | #003670 | 0.038 |
| Tritanopia (no blue cones) | #00414C | 0.093 |
| Achromatopsia (no color) | #393939 | 0.106 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2B3371
#2B3371
oklch(35.1% 0.106 274.1)
- #473900
#473900
oklch(34.9% 0.072 93.4)
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 #2B3371, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine Blue #01386A ΔE 0.041
- Twilight Blue #0A437A ΔE 0.050
- Prussian Blue #1D3557 ΔE 0.051
- Marine #042E60 ΔE 0.055
- Dark Slate Blue #483D8B ΔE 0.070
- Cobalt #1E488F ΔE 0.072
- Midnight Blue #191970 ΔE 0.073
- Dark Blue Grey #1F3B4D ΔE 0.075
Use #2B3371 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.