#173C6F
Closest named color: Marine Blue (#01386A). oklch(35.9% 0.098 257.3), rgb(23, 60, 111).
Aa
White text reads best on this color (10.98:1).
About this color
#173C6F is a dark, moderately saturated blue. In OKLCH its lightness is 36%, its chroma 0.098 and its hue 257°. Its hue sits on the cool side of the wheel. The nearest named color is Marine Blue (#01386A), ΔE 0.022 away. White text reads best on it, at 10.98:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | moderately saturated (0.098) |
| Temperature | cool |
| Nearest name | Marine Blue (#01386A) |
| Black text | 1.91:1 |
| White text | 10.98:1 |
Values
| HEX | #173C6F |
| RGB | rgb(23, 60, 111) |
| HSL | hsl(215, 66%, 26%) |
| OKLCH | oklch(35.9% 0.098 257.3) |
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 #173C6F | 10.98:1 | AAA | Lc -99.0 | Preferred for body text |
| Black text on #173C6F | 1.91:1 | Fails | Lc 8.8 | Not readable |
| #173C6F text on white | 10.98:1 | AAA | Lc 95.1 | Preferred for body text |
| #173C6F text on black | 1.91:1 | Fails | Lc -7.5 | 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
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E1EBF8
oklch(93.6% 0.021 254.9)
-
Step 200
200
#C9DBF5
oklch(88.6% 0.041 257.5)
-
Step 300
300
#A3C3F0
oklch(80.9% 0.073 256.9)
-
Step 400
400
#70A2E9
oklch(70.6% 0.118 257.2)
-
Step 500
500
#4A89E2
oklch(63.1% 0.15 257.4)
-
Step 600
600
#2A71D0
oklch(55.6% 0.163 257.1)
-
Step 700
700
#1D5EB4
oklch(49.1% 0.151 257.2)
-
Step 800
800
#1A4D92
oklch(42.6% 0.126 257.3)
-
Step 900
900 (this color)
#173C6F
oklch(35.9% 0.098 257.3)
-
Step 950
950
#112644
oklch(26.9% 0.062 257.5)
#173C6F 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) | #224171 | 0.020 |
| Deuteranopia (no green cones) | #11396E | 0.011 |
| Tritanopia (no blue cones) | #004850 | 0.075 |
| Achromatopsia (no color) | #3C3C3C | 0.098 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #173C6F
#173C6F
oklch(35.9% 0.098 257.3)
- #523700
#523700
oklch(35.9% 0.075 78.1)
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 #173C6F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine Blue #01386A ΔE 0.022
- Twilight Blue #0A437A ΔE 0.026
- Prussian Blue #1D3557 ΔE 0.044
- Marine #042E60 ΔE 0.052
- Dark Grey Blue #29465B ΔE 0.056
- Dark Blue Grey #1F3B4D ΔE 0.059
- Cobalt #1E488F ΔE 0.062
- Midnight Green #073B4C ΔE 0.064
Use #173C6F 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.