#2B3873
Closest named color: Twilight Blue (#0A437A). oklch(36.3% 0.102 271.2), rgb(43, 56, 115).
Aa
White text reads best on this color (10.96:1).
About this color
#2B3873 is a dark, moderately saturated blue. In OKLCH its lightness is 36%, its chroma 0.102 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.039 away. White text reads best on it, at 10.96:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | moderately saturated (0.102) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.91:1 |
| White text | 10.96:1 |
Values
| HEX | #2B3873 |
| RGB | rgb(43, 56, 115) |
| HSL | hsl(229, 46%, 31%) |
| OKLCH | oklch(36.3% 0.102 271.2) |
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 #2B3873 | 10.96:1 | AAA | Lc -99.0 | Preferred for body text |
| Black text on #2B3873 | 1.91:1 | Fails | Lc 8.8 | Not readable |
| #2B3873 text on white | 10.96:1 | AAA | Lc 95.1 | Preferred for body text |
| #2B3873 text on black | 1.91:1 | Fails | Lc -7.5 | 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
#F3F5FD
oklch(97.1% 0.011 274.9)
-
Step 100
100
#E4E9F9
oklch(93.5% 0.022 272.1)
-
Step 200
200
#CED8F6
oklch(88.4% 0.043 270.9)
-
Step 300
300
#AEBFF3
oklch(81% 0.076 270.6)
-
Step 400
400
#859BED
oklch(70.6% 0.123 271.5)
-
Step 500
500
#6880E7
oklch(63% 0.157 271.4)
-
Step 600
600
#5167D5
oklch(55.5% 0.17 271.3)
-
Step 700
700
#4255B9
oklch(49.1% 0.158 271.3)
-
Step 800
800
#364696
oklch(42.7% 0.132 271.3)
-
Step 900
900 (this color)
#2B3873
oklch(36.3% 0.102 271.2)
-
Step 950
950
#1B2346
oklch(26.9% 0.066 271.6)
#2B3873 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) | #1A4075 | 0.027 |
| Deuteranopia (no green cones) | #0C3972 | 0.030 |
| Tritanopia (no blue cones) | #004550 | 0.088 |
| Achromatopsia (no color) | #3C3C3C | 0.102 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2B3873
#2B3873
oklch(36.3% 0.102 271.2)
- #4C3C00
#4C3C00
oklch(36.3% 0.074 91.9)
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 #2B3873, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.039
- Marine Blue #01386A ΔE 0.041
- Prussian Blue #1D3557 ΔE 0.053
- Cobalt #1E488F ΔE 0.060
- Marine #042E60 ΔE 0.062
- Dark Slate Blue #483D8B ΔE 0.063
- Dark Grey Blue #29465B ΔE 0.066
- Light Navy #155084 ΔE 0.071
Use #2B3873 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.