#28317B
Closest named color: Marine Blue (#01386A). oklch(35.3% 0.125 273), rgb(40, 49, 123).
Aa
White text reads best on this color (11.56:1).
About this color
#28317B is a dark, moderately saturated blue. In OKLCH its lightness is 35%, its chroma 0.125 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Marine Blue (#01386A), ΔE 0.048 away. White text reads best on it, at 11.56:1.
| Hue family | Blues |
| Lightness | dark (35%) |
| Chroma | moderately saturated (0.125) |
| Temperature | cool |
| Nearest name | Marine Blue (#01386A) |
| Black text | 1.81:1 |
| White text | 11.56:1 |
Values
| HEX | #28317B |
| RGB | rgb(40, 49, 123) |
| HSL | hsl(233, 51%, 32%) |
| OKLCH | oklch(35.3% 0.125 273) |
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 #28317B | 11.56:1 | AAA | Lc -100.0 | Preferred for body text |
| Black text on #28317B | 1.81:1 | Fails | Lc 7.6 | Not readable |
| #28317B text on white | 11.56:1 | AAA | Lc 96.2 | Preferred for body text |
| #28317B 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
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E3E9FD
oklch(93.5% 0.028 272.5)
-
Step 200
200
#CDD8FC
oklch(88.5% 0.051 271.9)
-
Step 300
300
#ACBDFE
oklch(80.9% 0.094 272.8)
-
Step 400
400
#8298FD
oklch(70.7% 0.15 272.8)
-
Step 500
500
#667AFB
oklch(63.1% 0.192 273)
-
Step 600
600
#505FEA
oklch(55.6% 0.208 272.9)
-
Step 700
700
#424DCC
oklch(49.1% 0.194 273.1)
-
Step 800
800
#3640A5
oklch(42.7% 0.161 273.2)
-
Step 900
900 (this color)
#28317B
oklch(35.3% 0.125 273)
-
Step 950
950
#1A214C
oklch(26.8% 0.079 272.9)
#28317B 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) | #003D7D | 0.040 |
| Deuteranopia (no green cones) | #00357A | 0.034 |
| Tritanopia (no blue cones) | #004351 | 0.103 |
| Achromatopsia (no color) | #393939 | 0.125 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #28317B
#28317B
oklch(35.3% 0.125 273)
- #483A00
#483A00
oklch(35.3% 0.072 93.7)
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 #28317B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine Blue #01386A ΔE 0.048
- Twilight Blue #0A437A ΔE 0.052
- Marine #042E60 ΔE 0.062
- Midnight Blue #191970 ΔE 0.067
- Cobalt #1E488F ΔE 0.067
- Prussian Blue #1D3557 ΔE 0.067
- Dark Slate Blue #483D8B ΔE 0.068
- Royal #0C1793 ΔE 0.076
Use #28317B 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.