#373D7B
Closest named color: Dark Slate Blue (#483D8B). oklch(38.9% 0.104 276.3), rgb(55, 61, 123).
Aa
White text reads best on this color (9.92:1).
About this color
#373D7B is a dark, moderately saturated blue. In OKLCH its lightness is 39%, its chroma 0.104 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.038 away. White text reads best on it, at 9.92:1.
| Hue family | Blues |
| Lightness | dark (39%) |
| Chroma | moderately saturated (0.104) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 2.11:1 |
| White text | 9.92:1 |
Values
| HEX | #373D7B |
| RGB | rgb(55, 61, 123) |
| HSL | hsl(235, 38%, 35%) |
| OKLCH | oklch(38.9% 0.104 276.3) |
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 #373D7B | 9.92:1 | AAA | Lc -97.0 | Preferred for body text |
| Black text on #373D7B | 2.11:1 | Fails | Lc 11.1 | Not readable |
| #373D7B text on white | 9.92:1 | AAA | Lc 92.8 | Preferred for body text |
| #373D7B text on black | 2.11:1 | Fails | Lc -9.6 | 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
#F3F5FD
oklch(97.1% 0.011 274.9)
-
Step 100
100
#E5E9F9
oklch(93.6% 0.022 274.7)
-
Step 200
200
#D1D7F6
oklch(88.4% 0.043 276.8)
-
Step 300
300
#B3BDF3
oklch(80.9% 0.077 276.4)
-
Step 400
400
#8C99EE
oklch(70.8% 0.125 276.1)
-
Step 500
500
#727DE8
oklch(63.2% 0.159 276.4)
-
Step 600
600
#5C63D6
oklch(55.6% 0.174 276.5)
-
Step 700
700
#4C52B9
oklch(49.2% 0.16 276.3)
-
Step 800
800
#3E4396
oklch(42.6% 0.134 276.5)
-
Step 900
900 (this color)
#373D7B
oklch(38.9% 0.104 276.3)
-
Step 950
950
#1E2246
oklch(26.9% 0.066 276.2)
#373D7B 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) | #20467D | 0.034 |
| Deuteranopia (no green cones) | #18407A | 0.036 |
| Tritanopia (no blue cones) | #184B56 | 0.092 |
| Achromatopsia (no color) | #434343 | 0.104 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373D7B
#373D7B
oklch(38.9% 0.104 276.3)
- #514400
#514400
oklch(38.8% 0.08 96.7)
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 #373D7B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.038
- Twilight Blue #0A437A ΔE 0.044
- Cobalt #1E488F ΔE 0.047
- Blueberry #464196 ΔE 0.052
- Light Navy #155084 ΔE 0.059
- Dusk Blue #26538D ΔE 0.065
- Marine Blue #01386A ΔE 0.065
- Dark Grey Blue #29465B ΔE 0.069
Use #373D7B 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.