#3F377D
Closest named color: Dark Slate Blue (#483D8B). oklch(38.4% 0.114 284.8), rgb(63, 55, 125).
Aa
White text reads best on this color (10.22:1).
About this color
#3F377D is a dark, moderately saturated purple. In OKLCH its lightness is 38%, its chroma 0.114 and its hue 285°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.032 away. White text reads best on it, at 10.22:1.
| Hue family | Purples |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.114) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 2.05:1 |
| White text | 10.22:1 |
Values
| HEX | #3F377D |
| RGB | rgb(63, 55, 125) |
| HSL | hsl(247, 39%, 35%) |
| OKLCH | oklch(38.4% 0.114 284.8) |
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 #3F377D | 10.22:1 | AAA | Lc -97.6 | Preferred for body text |
| Black text on #3F377D | 2.05:1 | Fails | Lc 10.4 | Not readable |
| #3F377D text on white | 10.22:1 | AAA | Lc 93.5 | Preferred for body text |
| #3F377D text on black | 2.05:1 | Fails | Lc -9.0 | 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
#E8E8FA
oklch(93.6% 0.024 285.9)
-
Step 200
200
#D5D5F8
oklch(88.4% 0.048 285.4)
-
Step 300
300
#BAB9F6
oklch(80.8% 0.086 285.1)
-
Step 400
400
#9893F2
oklch(70.7% 0.137 284.7)
-
Step 500
500
#8175EE
oklch(63.2% 0.176 284.7)
-
Step 600
600
#6C5ADC
oklch(55.6% 0.191 284.7)
-
Step 700
700
#5B49BF
oklch(49.2% 0.177 284.8)
-
Step 800
800
#4A3D9A
oklch(42.8% 0.146 284.8)
-
Step 900
900 (this color)
#3F377D
oklch(38.4% 0.114 284.8)
-
Step 950
950
#242048
oklch(27.1% 0.072 285.1)
#3F377D 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) | #11437F | 0.057 |
| Deuteranopia (no green cones) | #0E3F7B | 0.058 |
| Tritanopia (no blue cones) | #2A4654 | 0.096 |
| Achromatopsia (no color) | #414141 | 0.115 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F377D
#3F377D
oklch(38.4% 0.114 284.8)
- #4A4500
#4A4500
oklch(38.3% 0.081 104.9)
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 #3F377D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.032
- Blueberry #464196 ΔE 0.049
- Cobalt #1E488F ΔE 0.061
- Twilight Blue #0A437A ΔE 0.062
- Marine Blue #01386A ΔE 0.076
- Light Navy #155084 ΔE 0.077
- Twilight #4E518B ΔE 0.079
- Dusk Blue #26538D ΔE 0.080
Use #3F377D 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.