#283666
Closest named color: Prussian Blue (#1D3557). oklch(34.7% 0.086 269.3), rgb(40, 54, 102).
Aa
White text reads best on this color (11.60:1).
About this color
#283666 is a dark, moderately saturated blue. In OKLCH its lightness is 35%, its chroma 0.086 and its hue 269°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.031 away. White text reads best on it, at 11.60:1.
| Hue family | Blues |
| Lightness | dark (35%) |
| Chroma | moderately saturated (0.086) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.80:1 |
| White text | 11.60:1 |
Values
| HEX | #283666 |
| RGB | rgb(40, 54, 102) |
| HSL | hsl(226, 44%, 28%) |
| OKLCH | oklch(34.7% 0.086 269.3) |
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 #283666 | 11.60:1 | AAA | Lc -100.2 | Preferred for body text |
| Black text on #283666 | 1.80:1 | Fails | Lc 7.4 | Not readable |
| #283666 text on white | 11.60:1 | AAA | Lc 96.5 | Preferred for body text |
| #283666 text on black | 1.80:1 | Fails | Lc 0.0 | 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
#F3F5FB
oklch(97% 0.008 271.3)
-
Step 100
100
#E5EAF7
oklch(93.7% 0.018 269.1)
-
Step 200
200
#CFD9F2
oklch(88.5% 0.036 268.3)
-
Step 300
300
#B0C0EB
oklch(81% 0.063 269)
-
Step 400
400
#879EE1
oklch(70.8% 0.102 269.2)
-
Step 500
500
#6A84D9
oklch(63.1% 0.132 269.5)
-
Step 600
600
#526CC6
oklch(55.6% 0.142 269.2)
-
Step 700
700
#435AAB
oklch(49.2% 0.132 269.2)
-
Step 800
800
#374A8B
oklch(42.8% 0.11 269.1)
-
Step 900
900 (this color)
#283666
oklch(34.7% 0.086 269.3)
-
Step 950
950
#1C2541
oklch(27.1% 0.054 269.1)
#283666 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) | #213C68 | 0.018 |
| Deuteranopia (no green cones) | #183665 | 0.019 |
| Tritanopia (no blue cones) | #004149 | 0.077 |
| Achromatopsia (no color) | #393939 | 0.086 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283666
#283666
oklch(34.7% 0.086 269.3)
- #483700
#483700
oklch(34.6% 0.071 89.4)
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 #283666, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.031
- Marine Blue #01386A ΔE 0.033
- Marine #042E60 ΔE 0.047
- Twilight Blue #0A437A ΔE 0.049
- Dark Blue Grey #1F3B4D ΔE 0.052
- Dark Grey Blue #29465B ΔE 0.058
- Midnight Green #073B4C ΔE 0.062
- Space Cadet #2B2D42 ΔE 0.065
Use #283666 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.