#283780
Closest named color: Twilight Blue (#0A437A). oklch(36.9% 0.124 270.4), rgb(40, 55, 128).
Aa
White text reads best on this color (10.77:1).
About this color
#283780 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.124 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.041 away. White text reads best on it, at 10.77:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.124) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.94:1 |
| White text | 10.77:1 |
Values
| HEX | #283780 |
| RGB | rgb(40, 55, 128) |
| HSL | hsl(230, 52%, 33%) |
| OKLCH | oklch(36.9% 0.124 270.4) |
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 #283780 | 10.77:1 | AAA | Lc -98.6 | Preferred for body text |
| Black text on #283780 | 1.94:1 | Fails | Lc 9.3 | Not readable |
| #283780 text on white | 10.77:1 | AAA | Lc 94.6 | Preferred for body text |
| #283780 text on black | 1.94:1 | 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
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E3E9FD
oklch(93.5% 0.028 272.5)
-
Step 200
200
#CCD8FC
oklch(88.5% 0.051 270.8)
-
Step 300
300
#A9BEFE
oklch(80.9% 0.094 270.2)
-
Step 400
400
#7E99FD
oklch(70.6% 0.149 270.8)
-
Step 500
500
#5F7CFB
oklch(63% 0.191 270.4)
-
Step 600
600
#4961EA
oklch(55.6% 0.207 270.5)
-
Step 700
700
#3B4FCB
oklch(49% 0.192 270.5)
-
Step 800
800
#3042A4
oklch(42.7% 0.159 270.3)
-
Step 900
900 (this color)
#283780
oklch(36.9% 0.124 270.4)
-
Step 950
950
#18224C
oklch(26.9% 0.079 270.3)
#283780 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) | #004283 | 0.037 |
| Deuteranopia (no green cones) | #003A7F | 0.031 |
| Tritanopia (no blue cones) | #004956 | 0.103 |
| Achromatopsia (no color) | #3E3E3E | 0.124 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283780
#283780
oklch(36.9% 0.124 270.4)
- #4F3D00
#4F3D00
oklch(36.9% 0.075 89.9)
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 #283780, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.041
- Cobalt #1E488F ΔE 0.050
- Marine Blue #01386A ΔE 0.052
- Dark Slate Blue #483D8B ΔE 0.056
- Blueberry #464196 ΔE 0.065
- Light Navy #155084 ΔE 0.070
- Sapphire #2138AB ΔE 0.071
- Marine #042E60 ΔE 0.073
Use #283780 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.