#283B7B
Closest named color: Twilight Blue (#0A437A). oklch(37.4% 0.111 268.2), rgb(40, 59, 123).
Aa
White text reads best on this color (10.49:1).
About this color
#283B7B is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.111 and its hue 268°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.030 away. White text reads best on it, at 10.49:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.111) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.00:1 |
| White text | 10.49:1 |
Values
| HEX | #283B7B |
| RGB | rgb(40, 59, 123) |
| HSL | hsl(226, 51%, 32%) |
| OKLCH | oklch(37.4% 0.111 268.2) |
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 #283B7B | 10.49:1 | AAA | Lc -98.1 | Preferred for body text |
| Black text on #283B7B | 2.00:1 | Fails | Lc 9.9 | Not readable |
| #283B7B text on white | 10.49:1 | AAA | Lc 94.1 | Preferred for body text |
| #283B7B text on black | 2.00:1 | Fails | Lc -8.5 | 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
#F2F5FD
oklch(97% 0.011 269.6)
-
Step 100
100
#E3EAFB
oklch(93.7% 0.024 267.9)
-
Step 200
200
#CCD9F9
oklch(88.6% 0.046 267.9)
-
Step 300
300
#AABFF7
oklch(80.9% 0.083 268.6)
-
Step 400
400
#7D9CF4
oklch(70.7% 0.134 268.2)
-
Step 500
500
#5E81F0
oklch(63.2% 0.171 268.1)
-
Step 600
600
#4667DE
oklch(55.6% 0.185 268.1)
-
Step 700
700
#3855C1
oklch(49.2% 0.172 268.1)
-
Step 800
800
#2E469C
oklch(42.7% 0.143 268)
-
Step 900
900 (this color)
#283B7B
oklch(37.4% 0.111 268.2)
-
Step 950
950
#182449
oklch(27.2% 0.071 268)
#283B7B 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) | #17437D | 0.025 |
| Deuteranopia (no green cones) | #013C7A | 0.030 |
| Tritanopia (no blue cones) | #004A55 | 0.093 |
| Achromatopsia (no color) | #3F3F3F | 0.111 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283B7B
#283B7B
oklch(37.4% 0.111 268.2)
- #523E00
#523E00
oklch(37.5% 0.077 88)
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 #283B7B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.030
- Cobalt #1E488F ΔE 0.046
- Marine Blue #01386A ΔE 0.046
- Dark Slate Blue #483D8B ΔE 0.056
- Light Navy #155084 ΔE 0.060
- Prussian Blue #1D3557 ΔE 0.066
- Blueberry #464196 ΔE 0.066
- Dark Grey Blue #29465B ΔE 0.071
Use #283B7B 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.