#40366C
Closest named color: Dark Slate Blue (#483D8B). oklch(37.1% 0.09 289.8), rgb(64, 54, 108).
Aa
White text reads best on this color (10.70:1).
About this color
#40366C is a dark, moderately saturated purple. In OKLCH its lightness is 37%, its chroma 0.090 and its hue 290°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.056 away. White text reads best on it, at 10.70:1.
| Hue family | Purples |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.090) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 1.96:1 |
| White text | 10.70:1 |
Values
| HEX | #40366C |
| RGB | rgb(64, 54, 108) |
| HSL | hsl(251, 33%, 32%) |
| OKLCH | oklch(37.1% 0.09 289.8) |
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 #40366C | 10.70:1 | AAA | Lc -98.6 | Preferred for body text |
| Black text on #40366C | 1.96:1 | Fails | Lc 9.2 | Not readable |
| #40366C text on white | 10.70:1 | AAA | Lc 94.7 | Preferred for body text |
| #40366C text on black | 1.96:1 | Fails | Lc -7.9 | 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
#F5F5FB
oklch(97.2% 0.008 286.3)
-
Step 100
100
#E9E8F6
oklch(93.6% 0.019 289.3)
-
Step 200
200
#D8D5F1
oklch(88.4% 0.038 290.5)
-
Step 300
300
#BFBAEA
oklch(80.9% 0.067 289.6)
-
Step 400
400
#9F95E0
oklch(70.7% 0.108 289.4)
-
Step 500
500
#8979D7
oklch(63.2% 0.138 289.7)
-
Step 600
600
#7460C4
oklch(55.7% 0.15 289.8)
-
Step 700
700
#614FA9
oklch(49.1% 0.139 289.5)
-
Step 800
800
#4F4189
oklch(42.7% 0.115 289.5)
-
Step 900
900 (this color)
#40366C
oklch(37.1% 0.09 289.8)
-
Step 950
950
#262140
oklch(27% 0.057 289.5)
#40366C 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) | #223F6E | 0.047 |
| Deuteranopia (no green cones) | #223D6B | 0.046 |
| Tritanopia (no blue cones) | #34414C | 0.075 |
| Achromatopsia (no color) | #3E3E3E | 0.091 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #40366C
#40366C
oklch(37.1% 0.09 289.8)
- #434300
#434300
oklch(37.1% 0.081 109.8)
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 #40366C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.056
- Prussian Blue #1D3557 ΔE 0.066
- Twilight Blue #0A437A ΔE 0.066
- Dark Grey Blue #29465B ΔE 0.069
- Marine Blue #01386A ΔE 0.070
- Blueberry #464196 ΔE 0.074
- Dark Blue Grey #1F3B4D ΔE 0.078
- Cobalt #1E488F ΔE 0.078
Use #40366C 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.