#283B73
Closest named color: Twilight Blue (#0A437A). oklch(36.8% 0.099 267.3), rgb(40, 59, 115).
Aa
White text reads best on this color (10.69:1).
About this color
#283B73 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.099 and its hue 267°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.031 away. White text reads best on it, at 10.69:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.099) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.96:1 |
| White text | 10.69:1 |
Values
| HEX | #283B73 |
| RGB | rgb(40, 59, 115) |
| HSL | hsl(225, 48%, 30%) |
| OKLCH | oklch(36.8% 0.099 267.3) |
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 #283B73 | 10.69:1 | AAA | Lc -98.5 | Preferred for body text |
| Black text on #283B73 | 1.96:1 | Fails | Lc 9.3 | Not readable |
| #283B73 text on white | 10.69:1 | AAA | Lc 94.6 | Preferred for body text |
| #283B73 text on black | 1.96:1 | Fails | Lc -8.0 | 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
#F2F5FC
oklch(97% 0.01 267.4)
-
Step 100
100
#E3EAF9
oklch(93.6% 0.022 265.8)
-
Step 200
200
#CDD9F5
oklch(88.5% 0.041 267.1)
-
Step 300
300
#ABC0F2
oklch(80.9% 0.075 267)
-
Step 400
400
#809DEB
oklch(70.6% 0.119 267.8)
-
Step 500
500
#6183E5
oklch(63.1% 0.152 267.5)
-
Step 600
600
#496AD3
oklch(55.6% 0.166 267.6)
-
Step 700
700
#3A58B7
oklch(49.1% 0.154 267.3)
-
Step 800
800
#304994
oklch(42.8% 0.127 267.1)
-
Step 900
900 (this color)
#283B73
oklch(36.8% 0.099 267.3)
-
Step 950
950
#192445
oklch(26.9% 0.063 268.1)
#283B73 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) | #204275 | 0.021 |
| Deuteranopia (no green cones) | #133B72 | 0.021 |
| Tritanopia (no blue cones) | #004851 | 0.085 |
| Achromatopsia (no color) | #3E3E3E | 0.099 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283B73
#283B73
oklch(36.8% 0.099 267.3)
- #503C00
#503C00
oklch(36.8% 0.075 87.4)
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 #283B73, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.031
- Marine Blue #01386A ΔE 0.039
- Prussian Blue #1D3557 ΔE 0.053
- Cobalt #1E488F ΔE 0.055
- Dark Grey Blue #29465B ΔE 0.060
- Light Navy #155084 ΔE 0.063
- Dark Slate Blue #483D8B ΔE 0.064
- Marine #042E60 ΔE 0.064
Use #283B73 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.