#373F9E
Closest named color: Blueberry (#464196). oklch(42% 0.152 274.1), rgb(55, 63, 158).
Aa
White text reads best on this color (8.87:1).
About this color
#373F9E is a dark, vivid blue. In OKLCH its lightness is 42%, its chroma 0.152 and its hue 274°. Its hue sits on the cool side of the wheel. The nearest named color is Blueberry (#464196), ΔE 0.027 away. White text reads best on it, at 8.87:1.
| Hue family | Blues |
| Lightness | dark (42%) |
| Chroma | vivid (0.152) |
| Temperature | cool |
| Nearest name | Blueberry (#464196) |
| Black text | 2.36:1 |
| White text | 8.87:1 |
Values
| HEX | #373F9E |
| RGB | rgb(55, 63, 158) |
| HSL | hsl(235, 48%, 42%) |
| OKLCH | oklch(42% 0.152 274.1) |
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 #373F9E | 8.87:1 | AAA | Lc -94.4 | Preferred for body text |
| Black text on #373F9E | 2.36:1 | Fails | Lc 14.1 | Not readable |
| #373F9E text on white | 8.87:1 | AAA | Lc 89.9 | Fine for body text |
| #373F9E text on black | 2.36:1 | Fails | Lc -12.4 | 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 800.
-
Step 50
50
#F3F5FE
oklch(97.1% 0.012 276.1)
-
Step 100
100
#E4E9FC
oklch(93.6% 0.026 274.1)
-
Step 200
200
#CFD7FB
oklch(88.5% 0.05 275.4)
-
Step 300
300
#AEBDFB
oklch(80.9% 0.089 273.7)
-
Step 400
400
#8698F9
oklch(70.7% 0.143 274.2)
-
Step 500
500
#6A7BF5
oklch(63.1% 0.181 274)
-
Step 600
600
#5460E4
oklch(55.5% 0.198 274.1)
-
Step 700
700
#454EC6
oklch(49% 0.184 274.1)
-
Step 800
800 (this color)
#373F9E
oklch(42% 0.152 274.1)
-
Step 900
900
#30387F
oklch(37.6% 0.119 274.3)
-
Step 950
950
#1C224A
oklch(27% 0.074 274)
#373F9E 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) | #004FA1 | 0.051 |
| Deuteranopia (no green cones) | #00459C | 0.043 |
| Tritanopia (no blue cones) | #005668 | 0.126 |
| Achromatopsia (no color) | #4A4A4A | 0.153 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373F9E
#373F9E
oklch(42% 0.152 274.1)
- #5C4C00
#5C4C00
oklch(42% 0.086 95.1)
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 #373F9E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blueberry #464196 ΔE 0.027
- Sapphire #2138AB ΔE 0.039
- Dark Slate Blue #483D8B ΔE 0.040
- Cobalt #1E488F ΔE 0.043
- Dusk Blue #26538D ΔE 0.064
- Blue Blue #2242C7 ΔE 0.069
- Majorelle Blue #3F37C9 ΔE 0.071
- Light Navy #155084 ΔE 0.072
Use #373F9E 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.