#373588
Closest named color: Dark Slate Blue (#483D8B). oklch(38.3% 0.135 279), rgb(55, 53, 136).
Aa
White text reads best on this color (10.35:1).
About this color
#373588 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.135 and its hue 279°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.037 away. White text reads best on it, at 10.35:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.135) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 2.02:1 |
| White text | 10.35:1 |
Values
| HEX | #373588 |
| RGB | rgb(55, 53, 136) |
| HSL | hsl(241, 44%, 37%) |
| OKLCH | oklch(38.3% 0.135 279) |
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 #373588 | 10.35:1 | AAA | Lc -97.7 | Preferred for body text |
| Black text on #373588 | 2.02:1 | Fails | Lc 10.3 | Not readable |
| #373588 text on white | 10.35:1 | AAA | Lc 93.7 | Preferred for body text |
| #373588 text on black | 2.02:1 | 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
#F3F5FF
oklch(97.2% 0.013 277.1)
-
Step 100
100
#E5E8FE
oklch(93.5% 0.03 279.6)
-
Step 200
200
#D0D6FF
oklch(88.5% 0.057 278.6)
-
Step 300
300
#B3BAFF
oklch(80.8% 0.098 279.5)
-
Step 400
400
#8D94FF
oklch(70.8% 0.155 278.8)
-
Step 500
500
#7474FF
oklch(63.2% 0.201 278.9)
-
Step 600
600
#5F56F1
oklch(55.6% 0.224 278.8)
-
Step 700
700
#5044D2
oklch(49.1% 0.209 279.2)
-
Step 800
800
#4139AA
oklch(42.7% 0.174 279.2)
-
Step 900
900 (this color)
#373588
oklch(38.3% 0.135 279)
-
Step 950
950
#1F1F4F
oklch(27% 0.086 279)
#373588 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) | #00438B | 0.054 |
| Deuteranopia (no green cones) | #003D86 | 0.051 |
| Tritanopia (no blue cones) | #044959 | 0.116 |
| Achromatopsia (no color) | #404040 | 0.135 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373588
#373588
oklch(38.3% 0.135 279)
- #4E4300
#4E4300
oklch(38.3% 0.079 98.6)
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 #373588, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.037
- Blueberry #464196 ΔE 0.046
- Cobalt #1E488F ΔE 0.053
- Twilight Blue #0A437A ΔE 0.061
- Sapphire #2138AB ΔE 0.063
- Marine Blue #01386A ΔE 0.077
- Light Navy #155084 ΔE 0.078
- Indigo Blue #3A18B1 ΔE 0.080
Use #373588 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.