#3F3178
Closest named color: Dark Slate Blue (#483D8B). oklch(36.9% 0.116 288.4), rgb(63, 49, 120).
Aa
White text reads best on this color (10.92:1).
About this color
#3F3178 is a dark, moderately saturated purple. In OKLCH its lightness is 37%, its chroma 0.116 and its hue 288°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.046 away. White text reads best on it, at 10.92:1.
| Hue family | Purples |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.116) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 1.92:1 |
| White text | 10.92:1 |
Values
| HEX | #3F3178 |
| RGB | rgb(63, 49, 120) |
| HSL | hsl(252, 42%, 33%) |
| OKLCH | oklch(36.9% 0.116 288.4) |
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 #3F3178 | 10.92:1 | AAA | Lc -98.9 | Preferred for body text |
| Black text on #3F3178 | 1.92:1 | Fails | Lc 8.9 | Not readable |
| #3F3178 text on white | 10.92:1 | AAA | Lc 95.0 | Preferred for body text |
| #3F3178 text on black | 1.92:1 | Fails | Lc -7.6 | 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
#F5F4FD
oklch(97% 0.012 291.3)
-
Step 100
100
#E9E8FA
oklch(93.7% 0.024 288.5)
-
Step 200
200
#D7D5F8
oklch(88.6% 0.048 288)
-
Step 300
300
#BEB8F6
oklch(80.9% 0.087 288.7)
-
Step 400
400
#9E91F2
oklch(70.8% 0.139 288.5)
-
Step 500
500
#8872ED
oklch(63.1% 0.178 288.4)
-
Step 600
600
#7356DB
oklch(55.5% 0.194 288.5)
-
Step 700
700
#6146BE
oklch(49.1% 0.179 288.3)
-
Step 800
800
#4F3A9A
oklch(42.7% 0.15 288.5)
-
Step 900
900 (this color)
#3F3178
oklch(36.9% 0.116 288.4)
-
Step 950
950
#261F48
oklch(27.1% 0.074 288.3)
#3F3178 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) | #053E7A | 0.067 |
| Deuteranopia (no green cones) | #063B76 | 0.066 |
| Tritanopia (no blue cones) | #2D414F | 0.097 |
| Achromatopsia (no color) | #3D3D3D | 0.117 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F3178
#3F3178
oklch(36.9% 0.116 288.4)
- #444200
#444200
oklch(36.9% 0.079 107.8)
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 #3F3178, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.046
- Blueberry #464196 ΔE 0.064
- Twilight Blue #0A437A ΔE 0.070
- Cobalt #1E488F ΔE 0.075
- Marine Blue #01386A ΔE 0.075
- Indigo #4B0082 ΔE 0.077
- Prussian Blue #1D3557 ΔE 0.080
- Royal Purple #4B006E ΔE 0.084
Use #3F3178 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.