#403F81
Closest named color: Dark Slate Blue (#483D8B). oklch(40.4% 0.108 281.1), rgb(64, 63, 129).
Aa
White text reads best on this color (9.34:1).
About this color
#403F81 is a dark, moderately saturated purple. In OKLCH its lightness is 40%, its chroma 0.108 and its hue 281°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.022 away. White text reads best on it, at 9.34:1.
| Hue family | Purples |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.108) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 2.24:1 |
| White text | 9.34:1 |
Values
| HEX | #403F81 |
| RGB | rgb(64, 63, 129) |
| HSL | hsl(241, 34%, 38%) |
| OKLCH | oklch(40.4% 0.108 281.1) |
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 #403F81 | 9.34:1 | AAA | Lc -95.7 | Preferred for body text |
| Black text on #403F81 | 2.24:1 | Fails | Lc 12.5 | Not readable |
| #403F81 text on white | 9.34:1 | AAA | Lc 91.4 | Preferred for body text |
| #403F81 text on black | 2.24:1 | Fails | Lc -10.9 | 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 800.
-
Step 50
50
#F4F5FB
oklch(97.1% 0.008 278.6)
-
Step 100
100
#E7E9F6
oklch(93.6% 0.018 279.1)
-
Step 200
200
#D4D7F1
oklch(88.5% 0.036 280.4)
-
Step 300
300
#B9BDE9
oklch(81% 0.062 280.8)
-
Step 400
400
#9599DE
oklch(70.6% 0.101 280.9)
-
Step 500
500
#7D7ED5
oklch(63% 0.129 281.5)
-
Step 600
600
#6766C3
oklch(55.6% 0.141 281.3)
-
Step 700
700
#5654A8
oklch(49.1% 0.131 281.5)
-
Step 800
800 (this color)
#403F81
oklch(40.4% 0.108 281.1)
-
Step 900
900
#3A3B6D
oklch(37.7% 0.084 280.7)
-
Step 950
950
#222340
oklch(27.1% 0.053 280.7)
#403F81 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) | #214983 | 0.043 |
| Deuteranopia (no green cones) | #1C4480 | 0.044 |
| Tritanopia (no blue cones) | #284D5A | 0.092 |
| Achromatopsia (no color) | #474747 | 0.108 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #403F81
#403F81
oklch(40.4% 0.108 281.1)
- #534A00
#534A00
oklch(40.5% 0.085 101.4)
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 #403F81, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.022
- Blueberry #464196 ΔE 0.036
- Cobalt #1E488F ΔE 0.047
- Twilight #4E518B ΔE 0.058
- Twilight Blue #0A437A ΔE 0.058
- Dusk Blue #26538D ΔE 0.060
- Light Navy #155084 ΔE 0.060
- Dusk #4E5481 ΔE 0.066
Use #403F81 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.