#2A3573
Closest named color: Marine Blue (#01386A). oklch(35.6% 0.107 272.3), rgb(42, 53, 115).
Aa
White text reads best on this color (11.31:1).
About this color
#2A3573 is a dark, moderately saturated blue. In OKLCH its lightness is 36%, its chroma 0.107 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Marine Blue (#01386A), ΔE 0.040 away. White text reads best on it, at 11.31:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | moderately saturated (0.107) |
| Temperature | cool |
| Nearest name | Marine Blue (#01386A) |
| Black text | 1.85:1 |
| White text | 11.31:1 |
Values
| HEX | #2A3573 |
| RGB | rgb(42, 53, 115) |
| HSL | hsl(231, 46%, 31%) |
| OKLCH | oklch(35.6% 0.107 272.3) |
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 #2A3573 | 11.31:1 | AAA | Lc -99.6 | Preferred for body text |
| Black text on #2A3573 | 1.85:1 | Fails | Lc 8.0 | Not readable |
| #2A3573 text on white | 11.31:1 | AAA | Lc 95.9 | Preferred for body text |
| #2A3573 text on black | 1.85:1 | 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
#E4E9FA
oklch(93.5% 0.024 272.8)
-
Step 200
200
#CFD8F7
oklch(88.5% 0.044 272.7)
-
Step 300
300
#AEBEF5
oklch(80.9% 0.08 271.9)
-
Step 400
400
#859AF0
oklch(70.6% 0.128 272.3)
-
Step 500
500
#697FEB
oklch(63.1% 0.163 272.3)
-
Step 600
600
#5265DA
oklch(55.6% 0.179 272.3)
-
Step 700
700
#4353BD
oklch(49.1% 0.166 272.3)
-
Step 800
800
#374599
oklch(42.8% 0.137 272.2)
-
Step 900
900 (this color)
#2A3573
oklch(35.6% 0.107 272.3)
-
Step 950
950
#1B2347
oklch(27% 0.068 271.8)
#2A3573 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) | #123E75 | 0.032 |
| Deuteranopia (no green cones) | #003772 | 0.036 |
| Tritanopia (no blue cones) | #00434E | 0.092 |
| Achromatopsia (no color) | #3A3A3A | 0.107 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2A3573
#2A3573
oklch(35.6% 0.107 272.3)
- #4A3A00
#4A3A00
oklch(35.6% 0.073 91.4)
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 #2A3573, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine Blue #01386A ΔE 0.040
- Twilight Blue #0A437A ΔE 0.044
- Prussian Blue #1D3557 ΔE 0.053
- Marine #042E60 ΔE 0.057
- Cobalt #1E488F ΔE 0.066
- Dark Slate Blue #483D8B ΔE 0.067
- Dark Grey Blue #29465B ΔE 0.073
- Dark Blue Grey #1F3B4D ΔE 0.075
Use #2A3573 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.