#373D77
Closest named color: Dark Slate Blue (#483D8B). oklch(38.6% 0.098 276.4), rgb(55, 61, 119).
Aa
White text reads best on this color (10.01:1).
About this color
#373D77 is a dark, moderately saturated blue. In OKLCH its lightness is 39%, its chroma 0.098 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.044 away. White text reads best on it, at 10.01:1.
| Hue family | Blues |
| Lightness | dark (39%) |
| Chroma | moderately saturated (0.098) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 2.09:1 |
| White text | 10.01:1 |
Values
| HEX | #373D77 |
| RGB | rgb(55, 61, 119) |
| HSL | hsl(234, 37%, 34%) |
| OKLCH | oklch(38.6% 0.098 276.4) |
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 #373D77 | 10.01:1 | AAA | Lc -97.2 | Preferred for body text |
| Black text on #373D77 | 2.09:1 | Fails | Lc 10.8 | Not readable |
| #373D77 text on white | 10.01:1 | AAA | Lc 93.1 | Preferred for body text |
| #373D77 text on black | 2.09:1 | Fails | Lc -9.4 | 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
#D1D7F5
oklch(88.4% 0.042 276.6)
-
Step 300
300
#B4BDF0
oklch(80.9% 0.073 276.8)
-
Step 400
400
#8D99E9
oklch(70.6% 0.118 276.4)
-
Step 500
500
#737EE2
oklch(63.1% 0.149 276.5)
-
Step 600
600
#5D65D0
oklch(55.6% 0.163 276.5)
-
Step 700
700
#4D53B4
oklch(49% 0.151 276.6)
-
Step 800
800
#3F4592
oklch(42.8% 0.125 276.4)
-
Step 900
900 (this color)
#373D77
oklch(38.6% 0.098 276.4)
-
Step 950
950
#1F2344
oklch(27.1% 0.061 276.3)
#373D77 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) | #234579 | 0.031 |
| Deuteranopia (no green cones) | #1D4076 | 0.032 |
| Tritanopia (no blue cones) | #1C4A54 | 0.087 |
| Achromatopsia (no color) | #424242 | 0.098 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373D77
#373D77
oklch(38.6% 0.098 276.4)
- #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 #373D77, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.044
- Twilight Blue #0A437A ΔE 0.044
- Cobalt #1E488F ΔE 0.051
- Blueberry #464196 ΔE 0.058
- Light Navy #155084 ΔE 0.060
- Marine Blue #01386A ΔE 0.062
- Dark Grey Blue #29465B ΔE 0.064
- Dusk Blue #26538D ΔE 0.067
Use #373D77 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.