#3F307A
Closest named color: Dark Slate Blue (#483D8B). oklch(36.9% 0.121 288.4), rgb(63, 48, 122).
Aa
White text reads best on this color (10.96:1).
About this color
#3F307A is a dark, moderately saturated purple. In OKLCH its lightness is 37%, its chroma 0.121 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 10.96:1.
| Hue family | Purples |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.121) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 1.91:1 |
| White text | 10.96:1 |
Values
| HEX | #3F307A |
| RGB | rgb(63, 48, 122) |
| HSL | hsl(252, 44%, 33%) |
| OKLCH | oklch(36.9% 0.121 288.4) |
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 #3F307A | 10.96:1 | AAA | Lc -99.0 | Preferred for body text |
| Black text on #3F307A | 1.91:1 | Fails | Lc 8.8 | Not readable |
| #3F307A text on white | 10.96:1 | AAA | Lc 95.1 | Preferred for body text |
| #3F307A text on black | 1.91:1 | 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
#E9E7FB
oklch(93.5% 0.027 290.5)
-
Step 200
200
#D7D5F9
oklch(88.6% 0.049 287.9)
-
Step 300
300
#BEB8F8
oklch(81% 0.09 288.5)
-
Step 400
400
#9E90F5
oklch(70.8% 0.145 288.5)
-
Step 500
500
#8870F1
oklch(63.1% 0.186 288.4)
-
Step 600
600
#7354DF
oklch(55.5% 0.202 288.3)
-
Step 700
700
#6144C2
oklch(49.2% 0.187 288.1)
-
Step 800
800
#4F399D
oklch(42.8% 0.155 288.2)
-
Step 900
900 (this color)
#3F307A
oklch(36.9% 0.121 288.4)
-
Step 950
950
#261E49
oklch(27% 0.077 288.7)
#3F307A 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) | #003E7C | 0.070 |
| Deuteranopia (no green cones) | #003B78 | 0.069 |
| Tritanopia (no blue cones) | #2C4150 | 0.100 |
| Achromatopsia (no color) | #3C3C3C | 0.121 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F307A
#3F307A
oklch(36.9% 0.121 288.4)
- #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 #3F307A, 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 0.063
- Twilight Blue #0A437A ΔE 0.072
- Indigo #4B0082 ΔE 0.074
- Cobalt #1E488F ΔE 0.075
- Marine Blue #01386A ΔE 0.077
- Royal Purple #4B006E ΔE 0.083
- Prussian Blue #1D3557 ΔE 0.083
Use #3F307A 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.