#283B7A
Closest named color: Twilight Blue (#0A437A). oklch(37.3% 0.11 268.1), rgb(40, 59, 122).
Aa
White text reads best on this color (10.51:1).
About this color
#283B7A is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.110 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 10.51:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.110) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.99:1 |
| White text | 10.51:1 |
Values
| HEX | #283B7A |
| RGB | rgb(40, 59, 122) |
| HSL | hsl(226, 51%, 32%) |
| OKLCH | oklch(37.3% 0.11 268.1) |
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 #283B7A | 10.51:1 | AAA | Lc -98.1 | Preferred for body text |
| Black text on #283B7A | 1.99:1 | Fails | Lc 9.8 | Not readable |
| #283B7A text on white | 10.51:1 | AAA | Lc 94.1 | Preferred for body text |
| #283B7A text on black | 1.99:1 | Fails | Lc -8.4 | 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
#E3EAFA
oklch(93.6% 0.023 266.9)
-
Step 200
200
#CCD9F8
oklch(88.5% 0.045 267.4)
-
Step 300
300
#AABFF7
oklch(80.9% 0.083 268.6)
-
Step 400
400
#7D9CF3
oklch(70.6% 0.132 268.1)
-
Step 500
500
#5E81EE
oklch(63.1% 0.168 268)
-
Step 600
600
#4667DD
oklch(55.5% 0.184 268.1)
-
Step 700
700
#3855C0
oklch(49.1% 0.171 268)
-
Step 800
800
#2F469B
oklch(42.7% 0.141 268.4)
-
Step 900
900 (this color)
#283B7A
oklch(37.3% 0.11 268.1)
-
Step 950
950
#182448
oklch(27.1% 0.069 267.8)
#283B7A 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) | #18437C | 0.025 |
| Deuteranopia (no green cones) | #043C79 | 0.028 |
| Tritanopia (no blue cones) | #004A54 | 0.093 |
| Achromatopsia (no color) | #3F3F3F | 0.110 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283B7A
#283B7A
oklch(37.3% 0.11 268.1)
- #513E00
#513E00
oklch(37.4% 0.076 89.1)
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 #283B7A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.030
- Marine Blue #01386A ΔE 0.045
- Cobalt #1E488F ΔE 0.047
- Dark Slate Blue #483D8B ΔE 0.057
- Light Navy #155084 ΔE 0.060
- Prussian Blue #1D3557 ΔE 0.064
- Blueberry #464196 ΔE 0.067
- Dark Grey Blue #29465B ΔE 0.069
Use #283B7A 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.