#2B3B78
Closest named color: Twilight Blue (#0A437A). oklch(37.4% 0.106 269.6), rgb(43, 59, 120).
Aa
White text reads best on this color (10.50:1).
About this color
#2B3B78 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.106 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.032 away. White text reads best on it, at 10.50:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.106) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.99:1 |
| White text | 10.50:1 |
Values
| HEX | #2B3B78 |
| RGB | rgb(43, 59, 120) |
| HSL | hsl(228, 47%, 32%) |
| OKLCH | oklch(37.4% 0.106 269.6) |
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 #2B3B78 | 10.50:1 | AAA | Lc -98.1 | Preferred for body text |
| Black text on #2B3B78 | 1.99:1 | Fails | Lc 9.8 | Not readable |
| #2B3B78 text on white | 10.50:1 | AAA | Lc 94.1 | Preferred for body text |
| #2B3B78 text on black | 1.99:1 | Fails | Lc -8.4 | 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
#F2F5FD
oklch(97% 0.011 269.6)
-
Step 100
100
#E4EAFA
oklch(93.7% 0.023 269.4)
-
Step 200
200
#CDD9F7
oklch(88.6% 0.043 268.2)
-
Step 300
300
#ACBFF5
oklch(80.9% 0.079 269.5)
-
Step 400
400
#819CF0
oklch(70.7% 0.127 269.4)
-
Step 500
500
#6381EB
oklch(63.2% 0.162 269.4)
-
Step 600
600
#4C67D9
oklch(55.6% 0.177 269.8)
-
Step 700
700
#3D55BC
oklch(49% 0.164 269.5)
-
Step 800
800
#334698
oklch(42.7% 0.136 269.9)
-
Step 900
900 (this color)
#2B3B78
oklch(37.4% 0.106 269.6)
-
Step 950
950
#1A2447
oklch(27.1% 0.066 269.6)
#2B3B78 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) | #1B437A | 0.026 |
| Deuteranopia (no green cones) | #0C3C77 | 0.028 |
| Tritanopia (no blue cones) | #004953 | 0.092 |
| Achromatopsia (no color) | #3F3F3F | 0.106 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2B3B78
#2B3B78
oklch(37.4% 0.106 269.6)
- #513E00
#513E00
oklch(37.4% 0.076 89.1)
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 #2B3B78, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.032
- Marine Blue #01386A ΔE 0.046
- Cobalt #1E488F ΔE 0.049
- Dark Slate Blue #483D8B ΔE 0.056
- Light Navy #155084 ΔE 0.061
- Prussian Blue #1D3557 ΔE 0.062
- Dark Grey Blue #29465B ΔE 0.066
- Blueberry #464196 ΔE 0.067
Use #2B3B78 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.