#171B47
Closest named color: Dark Indigo (#1F0954). oklch(24.8% 0.081 274.9), rgb(23, 27, 71).
Aa
White text reads best on this color (16.35:1).
About this color
#171B47 is a very dark, moderately saturated blue. In OKLCH its lightness is 25%, its chroma 0.081 and its hue 275°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Indigo (#1F0954), ΔE 0.046 away. White text reads best on it, at 16.35:1.
| Hue family | Blues |
| Lightness | very dark (25%) |
| Chroma | moderately saturated (0.081) |
| Temperature | cool |
| Nearest name | Dark Indigo (#1F0954) |
| Black text | 1.28:1 |
| White text | 16.35:1 |
Values
| HEX | #171B47 |
| RGB | rgb(23, 27, 71) |
| HSL | hsl(235, 51%, 18%) |
| OKLCH | oklch(24.8% 0.081 274.9) |
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 #171B47 | 16.35:1 | AAA | Lc -105.6 | Preferred for body text |
| Black text on #171B47 | 1.28:1 | Fails | Lc 0.0 | Not readable |
| #171B47 text on white | 16.35:1 | AAA | Lc 103.1 | Preferred for body text |
| #171B47 text on black | 1.28:1 | 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
#F3F5FE
oklch(97.1% 0.012 276.1)
-
Step 100
100
#E4E9FD
oklch(93.6% 0.028 274.7)
-
Step 200
200
#CED7FD
oklch(88.4% 0.053 274.8)
-
Step 300
300
#AEBCFF
oklch(80.9% 0.096 274.9)
-
Step 400
400
#8596FF
oklch(70.6% 0.154 274.8)
-
Step 500
500
#6A78FE
oklch(63.1% 0.197 274.8)
-
Step 600
600
#555CED
oklch(55.6% 0.214 274.9)
-
Step 700
700
#464ACE
oklch(49% 0.199 274.9)
-
Step 800
800
#393EA7
oklch(42.7% 0.165 274.8)
-
Step 900
900
#303684
oklch(37.6% 0.129 275)
-
Step 950
950 (this color)
#171B47
oklch(24.8% 0.081 274.9)
#171B47 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) | #002249 | 0.030 |
| Deuteranopia (no green cones) | #001E46 | 0.027 |
| Tritanopia (no blue cones) | #00252D | 0.070 |
| Achromatopsia (no color) | #202020 | 0.081 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #171B47
#171B47
oklch(24.8% 0.081 274.9)
- #292000
#292000
oklch(24.7% 0.051 93.6)
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 #171B47, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Indigo #1F0954 ΔE 0.046
- Oxford Blue #1B263B ΔE 0.046
- Navy Blue #001146 ΔE 0.047
- Dark #1B2431 ΔE 0.056
- Rich Black #0D1B2A ΔE 0.059
- Marine #042E60 ΔE 0.068
- Night Blue #040348 ΔE 0.070
- Space Cadet #2B2D42 ΔE 0.072
Use #171B47 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.