#373A99
Closest named color: Blueberry (#464196). oklch(40.6% 0.152 275.9), rgb(55, 58, 153).
Aa
White text reads best on this color (9.42:1).
About this color
#373A99 is a dark, vivid blue. In OKLCH its lightness is 41%, its chroma 0.152 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Blueberry (#464196), ΔE 0.031 away. White text reads best on it, at 9.42:1.
| Hue family | Blues |
| Lightness | dark (41%) |
| Chroma | vivid (0.152) |
| Temperature | cool |
| Nearest name | Blueberry (#464196) |
| Black text | 2.22:1 |
| White text | 9.42:1 |
Values
| HEX | #373A99 |
| RGB | rgb(55, 58, 153) |
| HSL | hsl(238, 47%, 41%) |
| OKLCH | oklch(40.6% 0.152 275.9) |
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 #373A99 | 9.42:1 | AAA | Lc -95.7 | Preferred for body text |
| Black text on #373A99 | 2.22:1 | Fails | Lc 12.6 | Not readable |
| #373A99 text on white | 9.42:1 | AAA | Lc 91.3 | Preferred for body text |
| #373A99 text on black | 2.22:1 | Fails | Lc -11.0 | 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
#E5E9FC
oklch(93.7% 0.026 276.4)
-
Step 200
200
#D0D7FA
oklch(88.5% 0.049 276.4)
-
Step 300
300
#B0BCFA
oklch(80.8% 0.089 275.8)
-
Step 400
400
#8997F8
oklch(70.7% 0.142 275.9)
-
Step 500
500
#6E7AF5
oklch(63.2% 0.182 275.7)
-
Step 600
600
#595FE3
oklch(55.6% 0.197 276)
-
Step 700
700
#494DC6
oklch(49.1% 0.184 275.8)
-
Step 800
800 (this color)
#373A99
oklch(40.6% 0.152 275.9)
-
Step 900
900
#32387F
oklch(37.7% 0.118 275.5)
-
Step 950
950
#1D214A
oklch(26.9% 0.075 275.9)
#373A99 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) | #004A9C | 0.053 |
| Deuteranopia (no green cones) | #004297 | 0.046 |
| Tritanopia (no blue cones) | #005264 | 0.127 |
| Achromatopsia (no color) | #464646 | 0.152 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373A99
#373A99
oklch(40.6% 0.152 275.9)
- #574800
#574800
oklch(40.5% 0.083 95.4)
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 #373A99, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blueberry #464196 ΔE 0.031
- Dark Slate Blue #483D8B ΔE 0.037
- Sapphire #2138AB ΔE 0.040
- Cobalt #1E488F ΔE 0.046
- Indigo Blue #3A18B1 ΔE 0.067
- Dusk Blue #26538D ΔE 0.072
- Twilight Blue #0A437A ΔE 0.072
- Imperial Purple #480CA8 ΔE 0.074
Use #373A99 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.