#17173A
Closest named color: Rich Black (#0D1B2A). oklch(22.7% 0.066 279.8), rgb(23, 23, 58).
Aa
White text reads best on this color (17.21:1).
About this color
#17173A is a very dark, muted blue. In OKLCH its lightness is 23%, its chroma 0.066 and its hue 280°. Its hue sits on the cool side of the wheel. The nearest named color is Rich Black (#0D1B2A), ΔE 0.040 away. White text reads best on it, at 17.21:1.
| Hue family | Blues |
| Lightness | very dark (23%) |
| Chroma | muted (0.066) |
| Temperature | cool |
| Nearest name | Rich Black (#0D1B2A) |
| Black text | 1.22:1 |
| White text | 17.21:1 |
Values
| HEX | #17173A |
| RGB | rgb(23, 23, 58) |
| HSL | hsl(240, 43%, 16%) |
| OKLCH | oklch(22.7% 0.066 279.8) |
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 #17173A | 17.21:1 | AAA | Lc -106.3 | Preferred for body text |
| Black text on #17173A | 1.22:1 | Fails | Lc 0.0 | Not readable |
| #17173A text on white | 17.21:1 | AAA | Lc 104.0 | Preferred for body text |
| #17173A text on black | 1.22:1 | 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
#F4F5FD
oklch(97.2% 0.011 280.5)
-
Step 100
100
#E6E9F9
oklch(93.6% 0.022 277.5)
-
Step 200
200
#D3D7F6
oklch(88.6% 0.043 279.7)
-
Step 300
300
#B6BCF3
oklch(81% 0.078 279.7)
-
Step 400
400
#9197ED
oklch(70.7% 0.125 279.6)
-
Step 500
500
#787BE7
oklch(63.1% 0.159 279.6)
-
Step 600
600
#6361D5
oklch(55.6% 0.173 279.9)
-
Step 700
700
#524FB9
oklch(49% 0.162 279.8)
-
Step 800
800
#434295
oklch(42.7% 0.133 279.7)
-
Step 900
900
#383977
oklch(37.8% 0.103 279.5)
-
Step 950
950 (this color)
#17173A
oklch(22.7% 0.066 279.8)
#17173A 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) | #051C3B | 0.027 |
| Deuteranopia (no green cones) | #031A39 | 0.028 |
| Tritanopia (no blue cones) | #081F25 | 0.058 |
| Achromatopsia (no color) | #1B1B1B | 0.066 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #17173A
#17173A
oklch(22.7% 0.066 279.8)
- #221C00
#221C00
oklch(22.7% 0.047 98)
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 #17173A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rich Black #0D1B2A ΔE 0.040
- Navy Blue #001146 ΔE 0.047
- Oxford Blue #1B263B ΔE 0.051
- Dark #1B2431 ΔE 0.052
- Dark Indigo #1F0954 ΔE 0.058
- Midnight Purple #280137 ΔE 0.062
- Very Dark Purple #2A0134 ΔE 0.065
- Night Blue #040348 ΔE 0.068
Use #17173A 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.