#283778
Closest named color: Twilight Blue (#0A437A). oklch(36.3% 0.112 270.2), rgb(40, 55, 120).
Aa
White text reads best on this color (11.00:1).
About this color
#283778 is a dark, moderately saturated blue. In OKLCH its lightness is 36%, its chroma 0.112 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.038 away. White text reads best on it, at 11.00:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | moderately saturated (0.112) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.90:1 |
| White text | 11.00:1 |
Values
| HEX | #283778 |
| RGB | rgb(40, 55, 120) |
| HSL | hsl(229, 50%, 31%) |
| OKLCH | oklch(36.3% 0.112 270.2) |
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 #283778 | 11.00:1 | AAA | Lc -99.0 | Preferred for body text |
| Black text on #283778 | 1.90:1 | Fails | Lc 8.7 | Not readable |
| #283778 text on white | 11.00:1 | AAA | Lc 95.2 | Preferred for body text |
| #283778 text on black | 1.90:1 | Fails | Lc -7.5 | 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
#CDD8F9
oklch(88.4% 0.047 270.8)
-
Step 300
300
#ABBFF8
oklch(81% 0.084 269.5)
-
Step 400
400
#809BF4
oklch(70.7% 0.134 269.9)
-
Step 500
500
#627FF0
oklch(63% 0.172 270)
-
Step 600
600
#4B65DF
oklch(55.6% 0.188 270.1)
-
Step 700
700
#3D53C1
oklch(49% 0.173 270.2)
-
Step 800
800
#32459C
oklch(42.7% 0.143 270)
-
Step 900
900 (this color)
#283778
oklch(36.3% 0.112 270.2)
-
Step 950
950
#192349
oklch(27% 0.072 270)
#283778 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) | #0F407A | 0.031 |
| Deuteranopia (no green cones) | #003977 | 0.032 |
| Tritanopia (no blue cones) | #004652 | 0.093 |
| Achromatopsia (no color) | #3C3C3C | 0.112 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283778
#283778
oklch(36.3% 0.112 270.2)
- #4D3C00
#4D3C00
oklch(36.4% 0.074 90.7)
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 #283778, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.038
- Marine Blue #01386A ΔE 0.042
- Cobalt #1E488F ΔE 0.057
- Prussian Blue #1D3557 ΔE 0.060
- Dark Slate Blue #483D8B ΔE 0.062
- Marine #042E60 ΔE 0.063
- Light Navy #155084 ΔE 0.071
- Blueberry #464196 ΔE 0.074
Use #283778 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.