#173F82
Closest named color: Twilight Blue (#0A437A). oklch(38.1% 0.122 260.2), rgb(23, 63, 130).
Aa
White text reads best on this color (10.14:1).
About this color
#173F82 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.122 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.020 away. White text reads best on it, at 10.14:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.122) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.06:1 |
| White text | 10.14:1 |
Values
| HEX | #173F82 |
| RGB | rgb(23, 63, 130) |
| HSL | hsl(218, 70%, 30%) |
| OKLCH | oklch(38.1% 0.122 260.2) |
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 #173F82 | 10.14:1 | AAA | Lc -97.2 | Preferred for body text |
| Black text on #173F82 | 2.06:1 | Fails | Lc 10.8 | Not readable |
| #173F82 text on white | 10.14:1 | AAA | Lc 93.1 | Preferred for body text |
| #173F82 text on black | 2.06:1 | Fails | Lc -9.4 | 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
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E0EBFC
oklch(93.7% 0.026 259)
-
Step 200
200
#C6DAFB
oklch(88.4% 0.051 260.4)
-
Step 300
300
#9EC2FC
oklch(80.9% 0.091 259.8)
-
Step 400
400
#69A0FB
oklch(70.8% 0.146 260)
-
Step 500
500
#4084F8
oklch(63% 0.187 260.4)
-
Step 600
600
#1E6AE7
oklch(55.5% 0.203 260.3)
-
Step 700
700
#1058C9
oklch(49.2% 0.188 260.2)
-
Step 800
800
#1149A2
oklch(42.8% 0.155 260)
-
Step 900
900 (this color)
#173F82
oklch(38.1% 0.122 260.2)
-
Step 950
950
#0E254B
oklch(27% 0.076 259.9)
#173F82 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) | #164784 | 0.023 |
| Deuteranopia (no green cones) | #003D81 | 0.015 |
| Tritanopia (no blue cones) | #004F5A | 0.094 |
| Achromatopsia (no color) | #414141 | 0.122 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #173F82
#173F82
oklch(38.1% 0.122 260.2)
- #583D00
#583D00
oklch(38.1% 0.079 80.4)
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 #173F82, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.020
- Cobalt #1E488F ΔE 0.034
- Marine Blue #01386A ΔE 0.048
- Light Navy #155084 ΔE 0.050
- Deep Sea Blue #015482 ΔE 0.061
- Dusk Blue #26538D ΔE 0.063
- Dark Slate Blue #483D8B ΔE 0.065
- Blueberry #464196 ΔE 0.069
Use #173F82 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.