#173786
Closest named color: Twilight Blue (#0A437A). oklch(36.6% 0.138 264), rgb(23, 55, 134).
Aa
White text reads best on this color (10.89:1).
About this color
#173786 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.138 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.041 away. White text reads best on it, at 10.89:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.138) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.92:1 |
| White text | 10.89:1 |
Values
| HEX | #173786 |
| RGB | rgb(23, 55, 134) |
| HSL | hsl(223, 71%, 31%) |
| OKLCH | oklch(36.6% 0.138 264) |
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 #173786 | 10.89:1 | AAA | Lc -98.6 | Preferred for body text |
| Black text on #173786 | 1.92:1 | Fails | Lc 9.2 | Not readable |
| #173786 text on white | 10.89:1 | AAA | Lc 94.7 | Preferred for body text |
| #173786 text on black | 1.92:1 | Fails | Lc -7.9 | 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 900.
-
Step 50
50
#F1F6FF
oklch(97.2% 0.013 262.4)
-
Step 100
100
#E0EAFF
oklch(93.6% 0.03 265.3)
-
Step 200
200
#C7DAFF
oklch(88.6% 0.055 263.7)
-
Step 300
300
#A1C0FF
oklch(80.8% 0.096 264.1)
-
Step 400
400
#6F9DFF
oklch(70.7% 0.152 263.9)
-
Step 500
500
#4A80FF
oklch(63.1% 0.198 264.2)
-
Step 600
600
#2962F7
oklch(55.5% 0.231 264.1)
-
Step 700
700
#1D50D7
oklch(49.1% 0.214 264.1)
-
Step 800
800
#1943AE
oklch(42.8% 0.177 264)
-
Step 900
900 (this color)
#173786
oklch(36.6% 0.138 264)
-
Step 950
950
#0F2350
oklch(27% 0.087 263.6)
#173786 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) | #004289 | 0.030 |
| Deuteranopia (no green cones) | #003884 | 0.014 |
| Tritanopia (no blue cones) | #004B59 | 0.107 |
| Achromatopsia (no color) | #3D3D3D | 0.138 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #173786
#173786
oklch(36.6% 0.138 264)
- #513B00
#513B00
oklch(36.7% 0.075 84.9)
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 #173786, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.041
- Cobalt #1E488F ΔE 0.050
- Marine Blue #01386A ΔE 0.051
- Sapphire #2138AB ΔE 0.063
- Royal #0C1793 ΔE 0.070
- Dark Slate Blue #483D8B ΔE 0.071
- Light Navy #155084 ΔE 0.072
- Marine #042E60 ΔE 0.073
Use #173786 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.