#373873
Closest named color: Twilight Blue (#0A437A). oklch(37.2% 0.099 279.7), rgb(55, 56, 115).
Aa
White text reads best on this color (10.62:1).
About this color
#373873 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.099 and its hue 280°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.050 away. White text reads best on it, at 10.62:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.099) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.97:1 |
| White text | 10.62:1 |
Values
| HEX | #373873 |
| RGB | rgb(55, 56, 115) |
| HSL | hsl(239, 35%, 33%) |
| OKLCH | oklch(37.2% 0.099 279.7) |
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 #373873 | 10.62:1 | AAA | Lc -98.4 | Preferred for body text |
| Black text on #373873 | 1.97:1 | Fails | Lc 9.4 | Not readable |
| #373873 text on white | 10.62:1 | AAA | Lc 94.5 | Preferred for body text |
| #373873 text on black | 1.97:1 | Fails | Lc -8.1 | 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
#E6E9F8
oklch(93.6% 0.02 276.9)
-
Step 200
200
#D3D7F5
oklch(88.5% 0.041 279.5)
-
Step 300
300
#B6BCF1
oklch(80.9% 0.075 279.5)
-
Step 400
400
#9298E9
oklch(70.7% 0.118 279.7)
-
Step 500
500
#797CE3
oklch(63.2% 0.152 279.8)
-
Step 600
600
#6363D0
oklch(55.6% 0.164 279.7)
-
Step 700
700
#5251B4
oklch(49% 0.153 279.6)
-
Step 800
800
#434392
oklch(42.7% 0.127 279.6)
-
Step 900
900 (this color)
#373873
oklch(37.2% 0.099 279.7)
-
Step 950
950
#212244
oklch(27% 0.062 280.1)
#373873 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) | #1D4175 | 0.038 |
| Deuteranopia (no green cones) | #183C72 | 0.038 |
| Tritanopia (no blue cones) | #204550 | 0.086 |
| Achromatopsia (no color) | #3E3E3E | 0.099 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373873
#373873
oklch(37.2% 0.099 279.7)
- #4A4100
#4A4100
oklch(37.3% 0.078 100.4)
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 #373873, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.050
- Dark Slate Blue #483D8B ΔE 0.051
- Marine Blue #01386A ΔE 0.058
- Cobalt #1E488F ΔE 0.063
- Prussian Blue #1D3557 ΔE 0.063
- Blueberry #464196 ΔE 0.067
- Dark Grey Blue #29465B ΔE 0.068
- Light Navy #155084 ΔE 0.073
Use #373873 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.