#3A3D81
Closest named color: Dark Slate Blue (#483D8B). oklch(39.5% 0.112 278), rgb(58, 61, 129).
Aa
White text reads best on this color (9.70:1).
About this color
#3A3D81 is a dark, moderately saturated blue. In OKLCH its lightness is 40%, its chroma 0.112 and its hue 278°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.028 away. White text reads best on it, at 9.70:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.112) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 2.16:1 |
| White text | 9.70:1 |
Values
| HEX | #3A3D81 |
| RGB | rgb(58, 61, 129) |
| HSL | hsl(237, 38%, 37%) |
| OKLCH | oklch(39.5% 0.112 278) |
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 #3A3D81 | 9.70:1 | AAA | Lc -96.5 | Preferred for body text |
| Black text on #3A3D81 | 2.16:1 | Fails | Lc 11.7 | Not readable |
| #3A3D81 text on white | 9.70:1 | AAA | Lc 92.3 | Preferred for body text |
| #3A3D81 text on black | 2.16:1 | Fails | Lc -10.1 | 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
#F3F5FD
oklch(97.1% 0.011 274.9)
-
Step 100
100
#E6E9FB
oklch(93.7% 0.024 278.4)
-
Step 200
200
#D1D7F9
oklch(88.5% 0.047 277.5)
-
Step 300
300
#B3BCF7
oklch(80.9% 0.084 277.6)
-
Step 400
400
#8E97F3
oklch(70.8% 0.134 278.1)
-
Step 500
500
#747AEF
oklch(63.2% 0.172 278)
-
Step 600
600
#5E5FDD
oklch(55.5% 0.188 278)
-
Step 700
700
#4E4EC0
oklch(49.1% 0.174 277.9)
-
Step 800
800
#40419B
oklch(42.8% 0.143 278)
-
Step 900
900 (this color)
#3A3D81
oklch(39.5% 0.112 278)
-
Step 950
950
#1F2148
oklch(26.9% 0.071 278.2)
#3A3D81 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) | #1A4783 | 0.042 |
| Deuteranopia (no green cones) | #114180 | 0.044 |
| Tritanopia (no blue cones) | #1A4C59 | 0.097 |
| Achromatopsia (no color) | #444444 | 0.113 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3A3D81
#3A3D81
oklch(39.5% 0.112 278)
- #524600
#524600
oklch(39.5% 0.082 98)
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 #3A3D81, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.028
- Blueberry #464196 ΔE 0.041
- Cobalt #1E488F ΔE 0.044
- Twilight Blue #0A437A ΔE 0.050
- Light Navy #155084 ΔE 0.060
- Dusk Blue #26538D ΔE 0.063
- Twilight #4E518B ΔE 0.067
- Deep Sea Blue #015482 ΔE 0.074
Use #3A3D81 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.