#283B80
Closest named color: Twilight Blue (#0A437A). oklch(37.8% 0.119 268.6), rgb(40, 59, 128).
Aa
White text reads best on this color (10.35:1).
About this color
#283B80 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.119 and its hue 269°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.033 away. White text reads best on it, at 10.35:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.119) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.02:1 |
| White text | 10.35:1 |
Values
| HEX | #283B80 |
| RGB | rgb(40, 59, 128) |
| HSL | hsl(227, 52%, 33%) |
| OKLCH | oklch(37.8% 0.119 268.6) |
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 #283B80 | 10.35:1 | AAA | Lc -97.8 | Preferred for body text |
| Black text on #283B80 | 2.02:1 | Fails | Lc 10.2 | Not readable |
| #283B80 text on white | 10.35:1 | AAA | Lc 93.7 | Preferred for body text |
| #283B80 text on black | 2.02:1 | Fails | Lc -8.8 | 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
#E2EAFC
oklch(93.6% 0.026 266.6)
-
Step 200
200
#CBD9FB
oklch(88.6% 0.049 267.7)
-
Step 300
300
#A8BFFB
oklch(80.9% 0.089 268.2)
-
Step 400
400
#7C9BF9
oklch(70.7% 0.142 268.8)
-
Step 500
500
#5C7FF6
oklch(63.1% 0.182 268.5)
-
Step 600
600
#4565E5
oklch(55.7% 0.197 268.6)
-
Step 700
700
#3752C7
oklch(49% 0.184 268.7)
-
Step 800
800
#2D44A1
oklch(42.6% 0.153 268.5)
-
Step 900
900 (this color)
#283B80
oklch(37.8% 0.119 268.6)
-
Step 950
950
#17234B
oklch(27% 0.076 268.4)
#283B80 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) | #104482 | 0.029 |
| Deuteranopia (no green cones) | #003C7F | 0.030 |
| Tritanopia (no blue cones) | #004B57 | 0.098 |
| Achromatopsia (no color) | #404040 | 0.119 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283B80
#283B80
oklch(37.8% 0.119 268.6)
- #533F00
#533F00
oklch(37.9% 0.077 88.3)
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 #283B80, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.033
- Cobalt #1E488F ΔE 0.041
- Dark Slate Blue #483D8B ΔE 0.052
- Marine Blue #01386A ΔE 0.052
- Light Navy #155084 ΔE 0.059
- Blueberry #464196 ΔE 0.060
- Dusk Blue #26538D ΔE 0.069
- Sapphire #2138AB ΔE 0.072
Use #283B80 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.