#373E75
Closest named color: Twilight Blue (#0A437A). oklch(38.7% 0.093 275.7), rgb(55, 62, 117).
Aa
White text reads best on this color (9.96:1).
About this color
#373E75 is a dark, moderately saturated blue. In OKLCH its lightness is 39%, its chroma 0.093 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.043 away. White text reads best on it, at 9.96:1.
| Hue family | Blues |
| Lightness | dark (39%) |
| Chroma | moderately saturated (0.093) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.10:1 |
| White text | 9.96:1 |
Values
| HEX | #373E75 |
| RGB | rgb(55, 62, 117) |
| HSL | hsl(233, 36%, 34%) |
| OKLCH | oklch(38.7% 0.093 275.7) |
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 #373E75 | 9.96:1 | AAA | Lc -97.1 | Preferred for body text |
| Black text on #373E75 | 2.10:1 | Fails | Lc 11.0 | Not readable |
| #373E75 text on white | 9.96:1 | AAA | Lc 93.0 | Preferred for body text |
| #373E75 text on black | 2.10:1 | Fails | Lc -9.5 | 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
#F3F5FC
oklch(97.1% 0.01 273.4)
-
Step 100
100
#E6E9F8
oklch(93.6% 0.02 276.9)
-
Step 200
200
#D1D8F3
oklch(88.5% 0.038 274.1)
-
Step 300
300
#B4BEEE
oklch(81% 0.069 275.6)
-
Step 400
400
#8D9AE6
oklch(70.6% 0.112 275.7)
-
Step 500
500
#737FDE
oklch(63% 0.143 276.1)
-
Step 600
600
#5C67CC
oklch(55.6% 0.155 275.5)
-
Step 700
700
#4C55B1
oklch(49.1% 0.145 275.5)
-
Step 800
800
#3E468F
oklch(42.7% 0.119 275.4)
-
Step 900
900 (this color)
#373E75
oklch(38.7% 0.093 275.7)
-
Step 950
950
#1F2343
oklch(27% 0.059 276.3)
#373E75 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) | #274577 | 0.026 |
| Deuteranopia (no green cones) | #214074 | 0.028 |
| Tritanopia (no blue cones) | #1D4A53 | 0.083 |
| Achromatopsia (no color) | #434343 | 0.093 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373E75
#373E75
oklch(38.7% 0.093 275.7)
- #514300
#514300
oklch(38.6% 0.079 95.5)
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 #373E75, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.043
- Dark Slate Blue #483D8B ΔE 0.046
- Cobalt #1E488F ΔE 0.052
- Light Navy #155084 ΔE 0.058
- Dark Grey Blue #29465B ΔE 0.059
- Blueberry #464196 ΔE 0.060
- Marine Blue #01386A ΔE 0.062
- Dusk Blue #26538D ΔE 0.066
Use #373E75 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.