#283B7F
Closest named color: Twilight Blue (#0A437A). oklch(37.7% 0.117 268.5), rgb(40, 59, 127).
Aa
White text reads best on this color (10.38:1).
About this color
#283B7F is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.117 and its hue 269°. 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 10.38:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.117) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.02:1 |
| White text | 10.38:1 |
Values
| HEX | #283B7F |
| RGB | rgb(40, 59, 127) |
| HSL | hsl(227, 52%, 33%) |
| OKLCH | oklch(37.7% 0.117 268.5) |
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 #283B7F | 10.38:1 | AAA | Lc -97.8 | Preferred for body text |
| Black text on #283B7F | 2.02:1 | Fails | Lc 10.1 | Not readable |
| #283B7F text on white | 10.38:1 | AAA | Lc 93.8 | Preferred for body text |
| #283B7F text on black | 2.02:1 | Fails | Lc -8.7 | 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
#E3EAFC
oklch(93.7% 0.025 268.8)
-
Step 200
200
#CBD9FA
oklch(88.5% 0.048 267.2)
-
Step 300
300
#A9BFFA
oklch(80.9% 0.087 268.6)
-
Step 400
400
#7C9BF8
oklch(70.6% 0.141 268.7)
-
Step 500
500
#5D7FF5
oklch(63.1% 0.18 268.7)
-
Step 600
600
#4565E4
oklch(55.6% 0.196 268.5)
-
Step 700
700
#3753C6
oklch(49.1% 0.182 268.4)
-
Step 800
800
#2E45A0
oklch(42.8% 0.15 268.5)
-
Step 900
900 (this color)
#283B7F
oklch(37.7% 0.117 268.5)
-
Step 950
950
#17234A
oklch(26.9% 0.074 268.3)
#283B7F 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) | #114481 | 0.029 |
| Deuteranopia (no green cones) | #003C7E | 0.030 |
| Tritanopia (no blue cones) | #004B57 | 0.097 |
| Achromatopsia (no color) | #404040 | 0.117 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283B7F
#283B7F
oklch(37.7% 0.117 268.5)
- #523F00
#523F00
oklch(37.8% 0.077 89.3)
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 #283B7F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.032
- Cobalt #1E488F ΔE 0.042
- Marine Blue #01386A ΔE 0.051
- Dark Slate Blue #483D8B ΔE 0.053
- Light Navy #155084 ΔE 0.059
- Blueberry #464196 ΔE 0.061
- Dusk Blue #26538D ΔE 0.069
- Prussian Blue #1D3557 ΔE 0.072
Use #283B7F 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.