#403F55
Closest named color: Dark Grey Blue (#29465B). oklch(37.8% 0.037 286.5), rgb(64, 63, 85).
Aa
White text reads best on this color (10.19:1).
About this color
#403F55 is a dark, muted purple. In OKLCH its lightness is 38%, its chroma 0.037 and its hue 287°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Grey Blue (#29465B), ΔE 0.036 away. White text reads best on it, at 10.19:1.
| Hue family | Purples |
| Lightness | dark (38%) |
| Chroma | muted (0.037) |
| Temperature | cool |
| Nearest name | Dark Grey Blue (#29465B) |
| Black text | 2.06:1 |
| White text | 10.19:1 |
Values
| HEX | #403F55 |
| RGB | rgb(64, 63, 85) |
| HSL | hsl(243, 15%, 29%) |
| OKLCH | oklch(37.8% 0.037 286.5) |
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 #403F55 | 10.19:1 | AAA | Lc -97.7 | Preferred for body text |
| Black text on #403F55 | 2.06:1 | Fails | Lc 10.3 | Not readable |
| #403F55 text on white | 10.19:1 | AAA | Lc 93.7 | Preferred for body text |
| #403F55 text on black | 2.06:1 | Fails | Lc -8.9 | 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 900.
-
Step 50
50
#F5F5F8
oklch(97.1% 0.004 286.3)
-
Step 100
100
#E9E9EF
oklch(93.6% 0.008 286.2)
-
Step 200
200
#D8D8E3
oklch(88.5% 0.015 286.1)
-
Step 300
300
#BFBED2
oklch(80.9% 0.028 288.1)
-
Step 400
400
#9E9DBC
oklch(70.7% 0.045 286.7)
-
Step 500
500
#8685AB
oklch(63.1% 0.057 285.9)
-
Step 600
600
#706E96
oklch(55.6% 0.062 286.5)
-
Step 700
700
#5E5C80
oklch(49.1% 0.057 286.6)
-
Step 800
800
#4D4B68
oklch(42.7% 0.048 287.4)
-
Step 900
900 (this color)
#403F55
oklch(37.8% 0.037 286.5)
-
Step 950
950
#252532
oklch(27% 0.024 284.7)
#403F55 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) | #394256 | 0.013 |
| Deuteranopia (no green cones) | #394154 | 0.013 |
| Tritanopia (no blue cones) | #3B4347 | 0.032 |
| Achromatopsia (no color) | #414141 | 0.037 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #403F55
#403F55
oklch(37.8% 0.037 286.5)
- #44432C
#44432C
oklch(37.7% 0.037 105.9)
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 #403F55, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Grey Blue #29465B ΔE 0.036
- Charcoal Grey #3C4142 ΔE 0.037
- Charcoal #264653 ΔE 0.041
- Onyx #343A40 ΔE 0.043
- Dark Blue Grey #1F3B4D ΔE 0.053
- Dark Slate Gray #2F4F4F ΔE 0.059
- Prussian Blue #1D3557 ΔE 0.064
- Gunmetal #293241 ΔE 0.065
Use #403F55 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.