#171939
Closest named color: Rich Black (#0D1B2A). oklch(23.1% 0.061 277.8), rgb(23, 25, 57).
Aa
White text reads best on this color (17.01:1).
About this color
#171939 is a very dark, muted blue. In OKLCH its lightness is 23%, its chroma 0.061 and its hue 278°. Its hue sits on the cool side of the wheel. The nearest named color is Rich Black (#0D1B2A), ΔE 0.036 away. White text reads best on it, at 17.01:1.
| Hue family | Blues |
| Lightness | very dark (23%) |
| Chroma | muted (0.061) |
| Temperature | cool |
| Nearest name | Rich Black (#0D1B2A) |
| Black text | 1.23:1 |
| White text | 17.01:1 |
Values
| HEX | #171939 |
| RGB | rgb(23, 25, 57) |
| HSL | hsl(236, 43%, 16%) |
| OKLCH | oklch(23.1% 0.061 277.8) |
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 #171939 | 17.01:1 | AAA | Lc -106.2 | Preferred for body text |
| Black text on #171939 | 1.23:1 | Fails | Lc 0.0 | Not readable |
| #171939 text on white | 17.01:1 | AAA | Lc 103.8 | Preferred for body text |
| #171939 text on black | 1.23:1 | 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
#F4F5FC
oklch(97.1% 0.009 279.7)
-
Step 100
100
#E6E9F8
oklch(93.6% 0.02 276.9)
-
Step 200
200
#D2D7F4
oklch(88.4% 0.04 277.8)
-
Step 300
300
#B5BDEF
oklch(80.9% 0.071 277.6)
-
Step 400
400
#9099E8
oklch(70.7% 0.116 278)
-
Step 500
500
#767EE1
oklch(63.2% 0.147 277.8)
-
Step 600
600
#6065CE
oklch(55.6% 0.159 277.8)
-
Step 700
700
#4F53B3
oklch(49.1% 0.149 277.6)
-
Step 800
800
#414491
oklch(42.7% 0.124 278)
-
Step 900
900
#363A73
oklch(37.6% 0.096 277.7)
-
Step 950
950 (this color)
#171939
oklch(23.1% 0.061 277.8)
#171939 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) | #0A1E3A | 0.022 |
| Deuteranopia (no green cones) | #071B38 | 0.022 |
| Tritanopia (no blue cones) | #092026 | 0.053 |
| Achromatopsia (no color) | #1C1C1C | 0.061 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #171939
#171939
oklch(23.1% 0.061 277.8)
- #231D00
#231D00
oklch(23.1% 0.048 98.3)
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 #171939, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rich Black #0D1B2A ΔE 0.036
- Oxford Blue #1B263B ΔE 0.044
- Dark #1B2431 ΔE 0.045
- Navy Blue #001146 ΔE 0.051
- Jet #212529 ΔE 0.061
- Dark Indigo #1F0954 ΔE 0.063
- Midnight Purple #280137 ΔE 0.067
- Very Dark Purple #2A0134 ΔE 0.069
Use #171939 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.