#173B60
Closest named color: Prussian Blue (#1D3557). oklch(34.6% 0.077 251.5), rgb(23, 59, 96).
Aa
White text reads best on this color (11.46:1).
About this color
#173B60 is a dark, moderately saturated blue. In OKLCH its lightness is 35%, its chroma 0.077 and its hue 252°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.022 away. White text reads best on it, at 11.46:1.
| Hue family | Blues |
| Lightness | dark (35%) |
| Chroma | moderately saturated (0.077) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.83:1 |
| White text | 11.46:1 |
Values
| HEX | #173B60 |
| RGB | rgb(23, 59, 96) |
| HSL | hsl(210, 61%, 23%) |
| OKLCH | oklch(34.6% 0.077 251.5) |
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 #173B60 | 11.46:1 | AAA | Lc -99.9 | Preferred for body text |
| Black text on #173B60 | 1.83:1 | Fails | Lc 7.7 | Not readable |
| #173B60 text on white | 11.46:1 | AAA | Lc 96.2 | Preferred for body text |
| #173B60 text on black | 1.83:1 | Fails | Lc 0.0 | 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 900.
-
Step 50
50
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E2EBF5
oklch(93.6% 0.017 250.8)
-
Step 200
200
#CADBEE
oklch(88.5% 0.032 251.1)
-
Step 300
300
#A6C4E5
oklch(80.9% 0.057 251)
-
Step 400
400
#75A5D9
oklch(70.8% 0.092 251.1)
-
Step 500
500
#508DCE
oklch(63.1% 0.117 251.5)
-
Step 600
600
#3176BB
oklch(55.6% 0.128 251.2)
-
Step 700
700
#2363A2
oklch(49.2% 0.12 251.4)
-
Step 800
800
#1F5183
oklch(42.7% 0.099 251.3)
-
Step 900
900 (this color)
#173B60
oklch(34.6% 0.077 251.5)
-
Step 950
950
#13283D
oklch(27.1% 0.048 250)
#173B60 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) | #2A3D62 | 0.023 |
| Deuteranopia (no green cones) | #20365F | 0.016 |
| Tritanopia (no blue cones) | #004449 | 0.059 |
| Achromatopsia (no color) | #393939 | 0.077 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #173B60
#173B60
oklch(34.6% 0.077 251.5)
- #513200
#513200
oklch(34.6% 0.074 71.8)
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 #173B60, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.022
- Marine Blue #01386A ΔE 0.026
- Dark Blue Grey #1F3B4D ΔE 0.034
- Midnight Green #073B4C ΔE 0.039
- Dark Grey Blue #29465B ΔE 0.045
- Marine #042E60 ΔE 0.046
- Twilight Blue #0A437A ΔE 0.047
- Charcoal #264653 ΔE 0.051
Use #173B60 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.