#173555
Closest named color: Prussian Blue (#1D3557). oklch(32.3% 0.068 252), rgb(23, 53, 85).
Aa
White text reads best on this color (12.52:1).
About this color
#173555 is a dark, muted blue. In OKLCH its lightness is 32%, its chroma 0.068 and its hue 252°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.008 away. White text reads best on it, at 12.52:1.
| Hue family | Blues |
| Lightness | dark (32%) |
| Chroma | muted (0.068) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.67:1 |
| White text | 12.52:1 |
Values
| HEX | #173555 |
| RGB | rgb(23, 53, 85) |
| HSL | hsl(211, 57%, 21%) |
| OKLCH | oklch(32.3% 0.068 252) |
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 #173555 | 12.52:1 | AAA | Lc -101.7 | Preferred for body text |
| Black text on #173555 | 1.67:1 | Fails | Lc 0.0 | Not readable |
| #173555 text on white | 12.52:1 | AAA | Lc 98.3 | Preferred for body text |
| #173555 text on black | 1.67:1 | 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 950.
-
Step 50
50
#F0F6FD
oklch(97.1% 0.011 252.1)
-
Step 100
100
#DFEBF9
oklch(93.5% 0.023 252.2)
-
Step 200
200
#C5DCF6
oklch(88.6% 0.044 251.5)
-
Step 300
300
#9BC5F3
oklch(81% 0.079 251.1)
-
Step 400
400
#61A5EE
oklch(70.8% 0.128 251.6)
-
Step 500
500
#2D8CE8
oklch(63.2% 0.163 251.7)
-
Step 600
600
#0074D0
oklch(55.6% 0.166 251.9)
-
Step 700
700
#0061B0
oklch(49% 0.147 252)
-
Step 800
800
#004F92
oklch(42.6% 0.129 252.3)
-
Step 900
900
#074278
oklch(37.6% 0.107 252.2)
-
Step 950
950 (this color)
#173555
oklch(32.3% 0.068 252)
#173555 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) | #273756 | 0.021 |
| Deuteranopia (no green cones) | #1E3154 | 0.014 |
| Tritanopia (no blue cones) | #003C41 | 0.051 |
| Achromatopsia (no color) | #343434 | 0.068 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #173555
#173555
oklch(32.3% 0.068 252)
- #492D02
#492D02
oklch(32.4% 0.068 71.5)
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 #173555, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.008
- Dark Blue Grey #1F3B4D ΔE 0.029
- Midnight Green #073B4C ΔE 0.030
- Marine #042E60 ΔE 0.036
- Marine Blue #01386A ΔE 0.038
- Gunmetal #293241 ΔE 0.039
- Space Cadet #2B2D42 ΔE 0.043
- Onyx #343A40 ΔE 0.059
Use #173555 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.