#373773
Closest named color: Twilight Blue (#0A437A). oklch(37% 0.101 280.3), rgb(55, 55, 115).
Aa
White text reads best on this color (10.73:1).
About this color
#373773 is a dark, moderately saturated purple. In OKLCH its lightness is 37%, its chroma 0.101 and its hue 280°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.051 away. White text reads best on it, at 10.73:1.
| Hue family | Purples |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.101) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.95:1 |
| White text | 10.73:1 |
Values
| HEX | #373773 |
| RGB | rgb(55, 55, 115) |
| HSL | hsl(240, 35%, 33%) |
| OKLCH | oklch(37% 0.101 280.3) |
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 #373773 | 10.73:1 | AAA | Lc -98.6 | Preferred for body text |
| Black text on #373773 | 1.95:1 | Fails | Lc 9.2 | Not readable |
| #373773 text on white | 10.73:1 | AAA | Lc 94.7 | Preferred for body text |
| #373773 text on black | 1.95:1 | 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
#F4F5FC
oklch(97.1% 0.009 279.7)
-
Step 100
100
#E7E9F9
oklch(93.7% 0.022 280.3)
-
Step 200
200
#D3D7F5
oklch(88.5% 0.041 279.5)
-
Step 300
300
#B7BCF1
oklch(81% 0.075 280.4)
-
Step 400
400
#9297EA
oklch(70.6% 0.121 280.2)
-
Step 500
500
#7A7BE4
oklch(63.1% 0.155 280.6)
-
Step 600
600
#6462D2
oklch(55.7% 0.168 280.2)
-
Step 700
700
#5350B6
oklch(49.1% 0.157 280.2)
-
Step 800
800
#444293
oklch(42.6% 0.13 280.5)
-
Step 900
900 (this color)
#373773
oklch(37% 0.101 280.3)
-
Step 950
950
#212245
oklch(27.1% 0.064 280)
#373773 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) | #1B4075 | 0.039 |
| Deuteranopia (no green cones) | #163C72 | 0.041 |
| Tritanopia (no blue cones) | #20444F | 0.087 |
| Achromatopsia (no color) | #3E3E3E | 0.101 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373773
#373773
oklch(37% 0.101 280.3)
- #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 #373773, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.051
- Dark Slate Blue #483D8B ΔE 0.052
- Marine Blue #01386A ΔE 0.058
- Prussian Blue #1D3557 ΔE 0.063
- Cobalt #1E488F ΔE 0.065
- Blueberry #464196 ΔE 0.068
- Dark Grey Blue #29465B ΔE 0.070
- Light Navy #155084 ΔE 0.075
Use #373773 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.