#373579
Closest named color: Dark Slate Blue (#483D8B). oklch(37% 0.113 280.7), rgb(55, 53, 121).
Aa
White text reads best on this color (10.78:1).
About this color
#373579 is a dark, moderately saturated purple. In OKLCH its lightness is 37%, its chroma 0.113 and its hue 281°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.047 away. White text reads best on it, at 10.78:1.
| Hue family | Purples |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.113) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 1.94:1 |
| White text | 10.78:1 |
Values
| HEX | #373579 |
| RGB | rgb(55, 53, 121) |
| HSL | hsl(242, 39%, 34%) |
| OKLCH | oklch(37% 0.113 280.7) |
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 #373579 | 10.78:1 | AAA | Lc -98.7 | Preferred for body text |
| Black text on #373579 | 1.94:1 | Fails | Lc 9.2 | Not readable |
| #373579 text on white | 10.78:1 | AAA | Lc 94.7 | Preferred for body text |
| #373579 text on black | 1.94:1 | Fails | Lc -7.9 | 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
#F4F5FD
oklch(97.2% 0.011 280.5)
-
Step 100
100
#E6E8FA
oklch(93.5% 0.024 280.9)
-
Step 200
200
#D3D6F8
oklch(88.5% 0.047 281.4)
-
Step 300
300
#B6BBF7
oklch(80.9% 0.085 280.6)
-
Step 400
400
#9295F3
oklch(70.7% 0.136 280.9)
-
Step 500
500
#7978EE
oklch(63.1% 0.173 280.6)
-
Step 600
600
#645DDC
oklch(55.5% 0.188 280.8)
-
Step 700
700
#534CBF
oklch(49% 0.174 280.5)
-
Step 800
800
#443F9B
oklch(42.7% 0.145 280.7)
-
Step 900
900 (this color)
#373579
oklch(37% 0.113 280.7)
-
Step 950
950
#212148
oklch(27.1% 0.071 280.6)
#373579 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) | #0D407B | 0.049 |
| Deuteranopia (no green cones) | #043B78 | 0.051 |
| Tritanopia (no blue cones) | #1B4451 | 0.097 |
| Achromatopsia (no color) | #3D3D3D | 0.113 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373579
#373579
oklch(37% 0.113 280.7)
- #494000
#494000
oklch(36.9% 0.077 100.3)
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 #373579, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.047
- Twilight Blue #0A437A ΔE 0.055
- Marine Blue #01386A ΔE 0.062
- Blueberry #464196 ΔE 0.062
- Cobalt #1E488F ΔE 0.062
- Prussian Blue #1D3557 ΔE 0.071
- Light Navy #155084 ΔE 0.078
- Marine #042E60 ΔE 0.079
Use #373579 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.