#373B75
Closest named color: Twilight Blue (#0A437A). oklch(38% 0.098 277.7), rgb(55, 59, 117).
Aa
White text reads best on this color (10.26:1).
About this color
#373B75 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.098 and its hue 278°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.046 away. White text reads best on it, at 10.26:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.098) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.04:1 |
| White text | 10.26:1 |
Values
| HEX | #373B75 |
| RGB | rgb(55, 59, 117) |
| HSL | hsl(236, 36%, 34%) |
| OKLCH | oklch(38% 0.098 277.7) |
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 #373B75 | 10.26:1 | AAA | Lc -97.7 | Preferred for body text |
| Black text on #373B75 | 2.04:1 | Fails | Lc 10.3 | Not readable |
| #373B75 text on white | 10.26:1 | AAA | Lc 93.7 | Preferred for body text |
| #373B75 text on black | 2.04:1 | Fails | Lc -8.8 | 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
#D2D7F5
oklch(88.5% 0.042 278)
-
Step 300
300
#B5BDF0
oklch(81% 0.073 277.7)
-
Step 400
400
#8F99E9
oklch(70.7% 0.117 277.5)
-
Step 500
500
#757DE2
oklch(63% 0.15 277.7)
-
Step 600
600
#5F64D0
oklch(55.5% 0.163 277.7)
-
Step 700
700
#4F53B4
oklch(49.2% 0.151 277.5)
-
Step 800
800
#414492
oklch(42.7% 0.126 278)
-
Step 900
900 (this color)
#373B75
oklch(38% 0.098 277.7)
-
Step 950
950
#202244
oklch(26.9% 0.063 278.8)
#373B75 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) | #214377 | 0.033 |
| Deuteranopia (no green cones) | #1B3E74 | 0.034 |
| Tritanopia (no blue cones) | #1E4852 | 0.086 |
| Achromatopsia (no color) | #414141 | 0.098 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373B75
#373B75
oklch(38% 0.098 277.7)
- #4E4200
#4E4200
oklch(38% 0.078 97.4)
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 #373B75, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.046
- Dark Slate Blue #483D8B ΔE 0.047
- Cobalt #1E488F ΔE 0.056
- Marine Blue #01386A ΔE 0.060
- Blueberry #464196 ΔE 0.062
- Dark Grey Blue #29465B ΔE 0.064
- Light Navy #155084 ΔE 0.065
- Prussian Blue #1D3557 ΔE 0.067
Use #373B75 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.