#403F66
Closest named color: Dark Grey Blue (#29465B). oklch(38.7% 0.066 284.1), rgb(64, 63, 102).
Aa
White text reads best on this color (9.90:1).
About this color
#403F66 is a dark, muted purple. In OKLCH its lightness is 39%, its chroma 0.066 and its hue 284°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Grey Blue (#29465B), ΔE 0.045 away. White text reads best on it, at 9.90:1.
| Hue family | Purples |
| Lightness | dark (39%) |
| Chroma | muted (0.066) |
| Temperature | cool |
| Nearest name | Dark Grey Blue (#29465B) |
| Black text | 2.12:1 |
| White text | 9.90:1 |
Values
| HEX | #403F66 |
| RGB | rgb(64, 63, 102) |
| HSL | hsl(242, 24%, 32%) |
| OKLCH | oklch(38.7% 0.066 284.1) |
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 #403F66 | 9.90:1 | AAA | Lc -97.1 | Preferred for body text |
| Black text on #403F66 | 2.12:1 | Fails | Lc 11.0 | Not readable |
| #403F66 text on white | 9.90:1 | AAA | Lc 92.9 | Preferred for body text |
| #403F66 text on black | 2.12:1 | Fails | Lc -9.5 | 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
#F5F5FA
oklch(97.2% 0.007 286.3)
-
Step 100
100
#E8E9F3
oklch(93.6% 0.013 281.6)
-
Step 200
200
#D6D7EB
oklch(88.4% 0.027 283.5)
-
Step 300
300
#BCBDE0
oklch(80.9% 0.049 284)
-
Step 400
400
#9A9AD0
oklch(70.6% 0.078 284.2)
-
Step 500
500
#8281C4
oklch(63.1% 0.1 283.8)
-
Step 600
600
#6C69B1
oklch(55.6% 0.11 284.1)
-
Step 700
700
#5A5798
oklch(49% 0.102 284)
-
Step 800
800
#4A487B
oklch(42.8% 0.083 284.1)
-
Step 900
900 (this color)
#403F66
oklch(38.7% 0.066 284.1)
-
Step 950
950
#24243A
oklch(27.1% 0.041 283.4)
#403F66 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) | #334468 | 0.023 |
| Deuteranopia (no green cones) | #324265 | 0.022 |
| Tritanopia (no blue cones) | #36464D | 0.057 |
| Achromatopsia (no color) | #434343 | 0.066 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #403F66
#403F66
oklch(38.7% 0.066 284.1)
- #4A4617
#4A4617
oklch(38.7% 0.066 104.4)
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 #403F66, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Grey Blue #29465B ΔE 0.045
- Charcoal #264653 ΔE 0.057
- Twilight Blue #0A437A ΔE 0.063
- Dark Slate Blue #483D8B ΔE 0.065
- Charcoal Grey #3C4142 ΔE 0.066
- Prussian Blue #1D3557 ΔE 0.067
- Dark Blue Grey #1F3B4D ΔE 0.067
- Onyx #343A40 ΔE 0.069
Use #403F66 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.