#403E78
Closest named color: Dark Slate Blue (#483D8B). oklch(39.6% 0.096 282.7), rgb(64, 62, 120).
Aa
White text reads best on this color (9.64:1).
About this color
#403E78 is a dark, moderately saturated purple. In OKLCH its lightness is 40%, its chroma 0.096 and its hue 283°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.035 away. White text reads best on it, at 9.64:1.
| Hue family | Purples |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.096) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 2.17:1 |
| White text | 9.64:1 |
Values
| HEX | #403E78 |
| RGB | rgb(64, 62, 120) |
| HSL | hsl(242, 32%, 36%) |
| OKLCH | oklch(39.6% 0.096 282.7) |
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 #403E78 | 9.64:1 | AAA | Lc -96.4 | Preferred for body text |
| Black text on #403E78 | 2.17:1 | Fails | Lc 11.8 | Not readable |
| #403E78 text on white | 9.64:1 | AAA | Lc 92.2 | Preferred for body text |
| #403E78 text on black | 2.17:1 | Fails | Lc -10.2 | 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
#F4F5FC
oklch(97.1% 0.009 279.7)
-
Step 100
100
#E7E8F8
oklch(93.5% 0.022 283.1)
-
Step 200
200
#D5D6F4
oklch(88.5% 0.041 284)
-
Step 300
300
#B9BBEE
oklch(80.8% 0.072 282.9)
-
Step 400
400
#9697E6
oklch(70.7% 0.115 282.5)
-
Step 500
500
#7E7BDF
oklch(63.1% 0.147 282.7)
-
Step 600
600
#6862CC
oklch(55.6% 0.159 282.5)
-
Step 700
700
#5750B1
oklch(49% 0.149 282.6)
-
Step 800
800
#47428F
oklch(42.6% 0.123 282.8)
-
Step 900
900 (this color)
#403E78
oklch(39.6% 0.096 282.7)
-
Step 950
950
#222243
oklch(27% 0.06 281.6)
#403E78 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) | #27477A | 0.039 |
| Deuteranopia (no green cones) | #244377 | 0.038 |
| Tritanopia (no blue cones) | #2E4A55 | 0.082 |
| Achromatopsia (no color) | #454545 | 0.096 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #403E78
#403E78
oklch(39.6% 0.096 282.7)
- #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 #403E78, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.035
- Blueberry #464196 ΔE 0.051
- Cobalt #1E488F ΔE 0.056
- Twilight Blue #0A437A ΔE 0.056
- Light Navy #155084 ΔE 0.063
- Twilight #4E518B ΔE 0.064
- Dusk Blue #26538D ΔE 0.066
- Dark Grey Blue #29465B ΔE 0.069
Use #403E78 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.