#374E80
Closest named color: Dusk Blue (#26538D). oklch(43% 0.088 264.3), rgb(55, 78, 128).
Aa
White text reads best on this color (8.19:1).
About this color
#374E80 is a dark, moderately saturated blue. In OKLCH its lightness is 43%, its chroma 0.088 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.027 away. White text reads best on it, at 8.19:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.088) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 2.56:1 |
| White text | 8.19:1 |
Values
| HEX | #374E80 |
| RGB | rgb(55, 78, 128) |
| HSL | hsl(221, 40%, 36%) |
| OKLCH | oklch(43% 0.088 264.3) |
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 #374E80 | 8.19:1 | AAA | Lc -92.8 | Preferred for body text |
| Black text on #374E80 | 2.56:1 | Fails | Lc 15.8 | Dividers and decoration only |
| #374E80 text on white | 8.19:1 | AAA | Lc 88.2 | Fine for body text |
| #374E80 text on black | 2.56:1 | Fails | Lc -14.0 | 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
#F3F5FA
oklch(97% 0.007 268.5)
-
Step 100
100
#E5EAF4
oklch(93.6% 0.015 264.5)
-
Step 200
200
#D0D9ED
oklch(88.5% 0.029 266.4)
-
Step 300
300
#B0C1E3
oklch(80.9% 0.052 264.2)
-
Step 400
400
#87A0D5
oklch(70.7% 0.083 264.8)
-
Step 500
500
#6988C9
oklch(63.1% 0.105 264.2)
-
Step 600
600
#5171B6
oklch(55.6% 0.114 264.2)
-
Step 700
700
#425E9D
oklch(49.1% 0.107 264.7)
-
Step 800
800 (this color)
#374E80
oklch(43% 0.088 264.3)
-
Step 900
900
#2F4166
oklch(37.8% 0.068 263.7)
-
Step 950
950
#1C263C
oklch(27.1% 0.044 265)
#374E80 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) | #3A5382 | 0.016 |
| Deuteranopia (no green cones) | #314C7F | 0.010 |
| Tritanopia (no blue cones) | #0C5961 | 0.078 |
| Achromatopsia (no color) | #4F4F4F | 0.088 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #374E80
#374E80
oklch(43% 0.088 264.3)
- #664B00
#664B00
oklch(43% 0.088 84.8)
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 #374E80, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.027
- Light Navy #155084 ΔE 0.030
- Light Navy Blue #2E5A88 ΔE 0.035
- Dusk #4E5481 ΔE 0.038
- Deep Sea Blue #015482 ΔE 0.039
- Twilight #4E518B ΔE 0.039
- Cobalt #1E488F ΔE 0.043
- Denim Blue #3B5B92 ΔE 0.045
Use #374E80 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.