#3F3B81
Closest named color: Dark Slate Blue (#483D8B). oklch(39.5% 0.114 282.4), rgb(63, 59, 129).
Aa
White text reads best on this color (9.74:1).
About this color
#3F3B81 is a dark, moderately saturated purple. In OKLCH its lightness is 40%, its chroma 0.114 and its hue 282°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.023 away. White text reads best on it, at 9.74:1.
| Hue family | Purples |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.114) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 2.15:1 |
| White text | 9.74:1 |
Values
| HEX | #3F3B81 |
| RGB | rgb(63, 59, 129) |
| HSL | hsl(243, 37%, 37%) |
| OKLCH | oklch(39.5% 0.114 282.4) |
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 #3F3B81 | 9.74:1 | AAA | Lc -96.6 | Preferred for body text |
| Black text on #3F3B81 | 2.15:1 | Fails | Lc 11.6 | Not readable |
| #3F3B81 text on white | 9.74:1 | AAA | Lc 92.4 | Preferred for body text |
| #3F3B81 text on black | 2.15:1 | Fails | Lc -10.0 | 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
#F4F5FD
oklch(97.2% 0.011 280.5)
-
Step 100
100
#E7E8FB
oklch(93.6% 0.026 283.5)
-
Step 200
200
#D4D6F9
oklch(88.6% 0.048 282.8)
-
Step 300
300
#B8BAF7
oklch(80.9% 0.086 282.8)
-
Step 400
400
#9494F3
oklch(70.6% 0.137 282.3)
-
Step 500
500
#7C76EF
oklch(63% 0.176 282.3)
-
Step 600
600
#675CDD
oklch(55.6% 0.19 282.1)
-
Step 700
700
#574AC0
oklch(49.1% 0.178 282.7)
-
Step 800
800
#463E9B
oklch(42.7% 0.146 282.1)
-
Step 900
900 (this color)
#3F3B81
oklch(39.5% 0.114 282.4)
-
Step 950
950
#222048
oklch(26.9% 0.072 282.7)
#3F3B81 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) | #174683 | 0.051 |
| Deuteranopia (no green cones) | #12427F | 0.052 |
| Tritanopia (no blue cones) | #264A58 | 0.097 |
| Achromatopsia (no color) | #444444 | 0.115 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F3B81
#3F3B81
oklch(39.5% 0.114 282.4)
- #4F4800
#4F4800
oklch(39.6% 0.083 103.2)
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 #3F3B81, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.023
- Blueberry #464196 ΔE 0.039
- Cobalt #1E488F ΔE 0.051
- Twilight Blue #0A437A ΔE 0.059
- Light Navy #155084 ΔE 0.068
- Twilight #4E518B ΔE 0.068
- Dusk Blue #26538D ΔE 0.069
- Dusk #4E5481 ΔE 0.077
Use #3F3B81 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.