#2B3171
Closest named color: Marine Blue (#01386A). oklch(34.6% 0.109 275.1), rgb(43, 49, 113).
Aa
White text reads best on this color (11.79:1).
About this color
#2B3171 is a dark, moderately saturated blue. In OKLCH its lightness is 35%, its chroma 0.109 and its hue 275°. Its hue sits on the cool side of the wheel. The nearest named color is Marine Blue (#01386A), ΔE 0.043 away. White text reads best on it, at 11.79:1.
| Hue family | Blues |
| Lightness | dark (35%) |
| Chroma | moderately saturated (0.109) |
| Temperature | cool |
| Nearest name | Marine Blue (#01386A) |
| Black text | 1.78:1 |
| White text | 11.79:1 |
Values
| HEX | #2B3171 |
| RGB | rgb(43, 49, 113) |
| HSL | hsl(235, 45%, 31%) |
| OKLCH | oklch(34.6% 0.109 275.1) |
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 #2B3171 | 11.79:1 | AAA | Lc -100.4 | Preferred for body text |
| Black text on #2B3171 | 1.78:1 | Fails | Lc 0.0 | Not readable |
| #2B3171 text on white | 11.79:1 | AAA | Lc 96.8 | Preferred for body text |
| #2B3171 text on black | 1.78:1 | 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
#D0D7F8
oklch(88.4% 0.046 276)
-
Step 300
300
#B1BDF6
oklch(80.9% 0.082 275.2)
-
Step 400
400
#8999F2
oklch(70.8% 0.131 274.8)
-
Step 500
500
#6E7CED
oklch(63% 0.168 275.2)
-
Step 600
600
#5863DB
oklch(55.6% 0.181 274.9)
-
Step 700
700
#4951BE
oklch(49.1% 0.169 275.1)
-
Step 800
800
#3C439A
oklch(42.8% 0.14 275.3)
-
Step 900
900 (this color)
#2B3171
oklch(34.6% 0.109 275.1)
-
Step 950
950
#1D2248
oklch(27% 0.07 275)
#2B3171 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) | #073B73 | 0.039 |
| Deuteranopia (no green cones) | #003570 | 0.039 |
| Tritanopia (no blue cones) | #00404C | 0.095 |
| Achromatopsia (no color) | #383838 | 0.109 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2B3171
#2B3171
oklch(34.6% 0.109 275.1)
- #453900
#453900
oklch(34.7% 0.071 95.8)
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 #2B3171, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine Blue #01386A ΔE 0.043
- Prussian Blue #1D3557 ΔE 0.053
- Marine #042E60 ΔE 0.053
- Twilight Blue #0A437A ΔE 0.054
- Midnight Blue #191970 ΔE 0.068
- Dark Slate Blue #483D8B ΔE 0.073
- Cobalt #1E488F ΔE 0.076
- Dark Blue Grey #1F3B4D ΔE 0.077
Use #2B3171 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.