#172F55
Closest named color: Prussian Blue (#1D3557). oklch(30.8% 0.075 259.2), rgb(23, 47, 85).
Aa
White text reads best on this color (13.33:1).
About this color
#172F55 is a dark, moderately saturated blue. In OKLCH its lightness is 31%, its chroma 0.075 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.021 away. White text reads best on it, at 13.33:1.
| Hue family | Blues |
| Lightness | dark (31%) |
| Chroma | moderately saturated (0.075) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.57:1 |
| White text | 13.33:1 |
Values
| HEX | #172F55 |
| RGB | rgb(23, 47, 85) |
| HSL | hsl(217, 57%, 21%) |
| OKLCH | oklch(30.8% 0.075 259.2) |
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 #172F55 | 13.33:1 | AAA | Lc -102.8 | Preferred for body text |
| Black text on #172F55 | 1.57:1 | Fails | Lc 0.0 | Not readable |
| #172F55 text on white | 13.33:1 | AAA | Lc 99.6 | Preferred for body text |
| #172F55 text on black | 1.57:1 | 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
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E0EBFC
oklch(93.7% 0.026 259)
-
Step 200
200
#C6DBFA
oklch(88.6% 0.048 258)
-
Step 300
300
#9EC2FA
oklch(80.8% 0.089 259.1)
-
Step 400
400
#69A0F8
oklch(70.6% 0.142 259.4)
-
Step 500
500
#3F86F5
oklch(63.2% 0.181 259.2)
-
Step 600
600
#1B6CE4
oklch(55.6% 0.198 259.3)
-
Step 700
700
#0C59C6
oklch(49.1% 0.184 259.3)
-
Step 800
800
#0F4AA0
oklch(42.8% 0.151 259.1)
-
Step 900
900
#153F7F
oklch(37.8% 0.118 259)
-
Step 950
950 (this color)
#172F55
oklch(30.8% 0.075 259.2)
#172F55 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) | #1D3256 | 0.013 |
| Deuteranopia (no green cones) | #142D54 | 0.008 |
| Tritanopia (no blue cones) | #00383D | 0.062 |
| Achromatopsia (no color) | #2F2F2F | 0.075 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #172F55
#172F55
oklch(30.8% 0.075 259.2)
- #412B00
#412B00
oklch(30.8% 0.064 78.5)
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 #172F55, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.021
- Marine #042E60 ΔE 0.025
- Space Cadet #2B2D42 ΔE 0.042
- Marine Blue #01386A ΔE 0.043
- Gunmetal #293241 ΔE 0.046
- Midnight Green #073B4C ΔE 0.047
- Dark Blue Grey #1F3B4D ΔE 0.047
- Oxford Blue #1B263B ΔE 0.051
Use #172F55 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.