#0A171F
Closest named color: Rich Black (#0D1B2A). oklch(19.7% 0.024 236.9), rgb(10, 23, 31).
Aa
White text reads best on this color (18.17:1).
About this color
#0A171F is a very dark close to neutral grey. In OKLCH its lightness is 20%, its chroma 0.024. It has too little chroma to lean warm or cool. The nearest named color is Rich Black (#0D1B2A), ΔE 0.025 away. White text reads best on it, at 18.17:1.
| Hue family | Neutrals |
| Lightness | very dark (20%) |
| Chroma | close to neutral grey (0.024) |
| Temperature | neutral |
| Nearest name | Rich Black (#0D1B2A) |
| Black text | 1.15:1 |
| White text | 18.17:1 |
Values
| HEX | #0A171F |
| RGB | rgb(10, 23, 31) |
| HSL | hsl(203, 51%, 8%) |
| OKLCH | oklch(19.7% 0.024 236.9) |
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 #0A171F | 18.17:1 | AAA | Lc -107.0 | Preferred for body text |
| Black text on #0A171F | 1.15:1 | Fails | Lc 0.0 | Not readable |
| #0A171F text on white | 18.17:1 | AAA | Lc 104.8 | Preferred for body text |
| #0A171F text on black | 1.15:1 | 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
#F3F6F8
oklch(97.1% 0.004 236.5)
-
Step 100
100
#E5EBEF
oklch(93.7% 0.008 236.6)
-
Step 200
200
#D0DBE3
oklch(88.5% 0.016 239.1)
-
Step 300
300
#B0C4D1
oklch(80.9% 0.029 236.3)
-
Step 400
400
#86A6BA
oklch(70.8% 0.046 235.7)
-
Step 500
500
#678FA9
oklch(63% 0.059 237.4)
-
Step 600
600
#4D7994
oklch(55.5% 0.064 236.5)
-
Step 700
700
#3E667F
oklch(49.1% 0.06 237.2)
-
Step 800
800
#345367
oklch(42.7% 0.05 237.8)
-
Step 900
900
#2D4554
oklch(37.7% 0.039 236.7)
-
Step 950
950 (this color)
#0A171F
oklch(19.7% 0.024 236.9)
#0A171F 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) | #13171F | 0.014 |
| Deuteranopia (no green cones) | #10151F | 0.011 |
| Tritanopia (no blue cones) | #02191A | 0.019 |
| Achromatopsia (no color) | #161616 | 0.025 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #0A171F
#0A171F
oklch(19.7% 0.024 236.9)
- #1E120A
#1E120A
oklch(19.6% 0.025 54.4)
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 #0A171F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rich Black #0D1B2A ΔE 0.025
- Rich Navy #001219 ΔE 0.029
- Almost Black #070D0D ΔE 0.048
- Dark #1B2431 ΔE 0.062
- Jet #212529 ΔE 0.067
- Oxford Blue #1B263B ΔE 0.076
- Navy Blue #001146 ΔE 0.082
- Dark Navy #000435 ΔE 0.083
Use #0A171F 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.