#374378
Closest named color: Twilight Blue (#0A437A). oklch(40% 0.09 272.1), rgb(55, 67, 120).
Aa
White text reads best on this color (9.38:1).
About this color
#374378 is a dark, moderately saturated blue. In OKLCH its lightness is 40%, its chroma 0.090 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.042 away. White text reads best on it, at 9.38:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.090) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.23:1 |
| White text | 9.38:1 |
Values
| HEX | #374378 |
| RGB | rgb(55, 67, 120) |
| HSL | hsl(229, 37%, 34%) |
| OKLCH | oklch(40% 0.09 272.1) |
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 #374378 | 9.38:1 | AAA | Lc -95.9 | Preferred for body text |
| Black text on #374378 | 2.23:1 | Fails | Lc 12.4 | Not readable |
| #374378 text on white | 9.38:1 | AAA | Lc 91.6 | Preferred for body text |
| #374378 text on black | 2.23:1 | Fails | Lc -10.8 | 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
#F3F5FC
oklch(97.1% 0.01 273.4)
-
Step 100
100
#E5E9F7
oklch(93.5% 0.019 273.2)
-
Step 200
200
#D0D8F3
oklch(88.5% 0.038 272.5)
-
Step 300
300
#B1BFED
oklch(81% 0.067 271.6)
-
Step 400
400
#899CE5
oklch(70.7% 0.109 272.2)
-
Step 500
500
#6D82DD
oklch(63.2% 0.139 272.1)
-
Step 600
600
#5669CA
oklch(55.5% 0.151 272.3)
-
Step 700
700
#4657AF
oklch(49% 0.141 272)
-
Step 800
800
#3A488E
oklch(42.8% 0.116 272.1)
-
Step 900
900 (this color)
#374378
oklch(40% 0.09 272.1)
-
Step 950
950
#1D2442
oklch(27% 0.057 272.2)
#374378 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) | #2D497A | 0.020 |
| Deuteranopia (no green cones) | #264477 | 0.021 |
| Tritanopia (no blue cones) | #1A4E57 | 0.080 |
| Achromatopsia (no color) | #464646 | 0.091 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #374378
#374378
oklch(40% 0.09 272.1)
- #574600
#574600
oklch(40% 0.082 93)
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 #374378, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.042
- Cobalt #1E488F ΔE 0.045
- Dark Slate Blue #483D8B ΔE 0.045
- Light Navy #155084 ΔE 0.046
- Dusk Blue #26538D ΔE 0.053
- Blueberry #464196 ΔE 0.056
- Dark Grey Blue #29465B ΔE 0.057
- Deep Sea Blue #015482 ΔE 0.058
Use #374378 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.