#373E72
Closest named color: Twilight Blue (#0A437A). oklch(38.5% 0.088 275.7), rgb(55, 62, 114).
Aa
White text reads best on this color (10.02:1).
About this color
#373E72 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.088 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.044 away. White text reads best on it, at 10.02:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.088) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.09:1 |
| White text | 10.02:1 |
Values
| HEX | #373E72 |
| RGB | rgb(55, 62, 114) |
| HSL | hsl(233, 35%, 33%) |
| OKLCH | oklch(38.5% 0.088 275.7) |
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 #373E72 | 10.02:1 | AAA | Lc -97.3 | Preferred for body text |
| Black text on #373E72 | 2.09:1 | Fails | Lc 10.8 | Not readable |
| #373E72 text on white | 10.02:1 | AAA | Lc 93.1 | Preferred for body text |
| #373E72 text on black | 2.09:1 | Fails | Lc -9.3 | 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
#E6E9F7
oklch(93.6% 0.019 276.3)
-
Step 200
200
#D2D8F2
oklch(88.6% 0.036 275.3)
-
Step 300
300
#B4BEEC
oklch(80.9% 0.066 275.3)
-
Step 400
400
#8E9BE3
oklch(70.8% 0.106 275.5)
-
Step 500
500
#7380DA
oklch(63% 0.136 275.6)
-
Step 600
600
#5D68C8
oklch(55.6% 0.147 275.6)
-
Step 700
700
#4D56AD
oklch(49.1% 0.137 275.7)
-
Step 800
800
#3F478C
oklch(42.8% 0.113 275.6)
-
Step 900
900 (this color)
#373E72
oklch(38.5% 0.088 275.7)
-
Step 950
950
#1F2341
oklch(26.9% 0.056 276.2)
#373E72 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) | #294574 | 0.025 |
| Deuteranopia (no green cones) | #234071 | 0.026 |
| Tritanopia (no blue cones) | #204952 | 0.078 |
| Achromatopsia (no color) | #424242 | 0.088 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373E72
#373E72
oklch(38.5% 0.088 275.7)
- #504300
#504300
oklch(38.5% 0.079 96.5)
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 #373E72, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.044
- Dark Slate Blue #483D8B ΔE 0.051
- Dark Grey Blue #29465B ΔE 0.055
- Cobalt #1E488F ΔE 0.056
- Light Navy #155084 ΔE 0.060
- Marine Blue #01386A ΔE 0.061
- Blueberry #464196 ΔE 0.065
- Prussian Blue #1D3557 ΔE 0.065
Use #373E72 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.