#17559F
Closest named color: Dusk Blue (#26538D). oklch(45.4% 0.135 255.8), rgb(23, 85, 159).
Aa
White text reads best on this color (7.40:1).
About this color
#17559F is a medium-dark, moderately saturated blue. In OKLCH its lightness is 45%, its chroma 0.135 and its hue 256°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.030 away. White text reads best on it, at 7.40:1.
| Hue family | Blues |
| Lightness | medium-dark (45%) |
| Chroma | moderately saturated (0.135) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 2.83:1 |
| White text | 7.40:1 |
Values
| HEX | #17559F |
| RGB | rgb(23, 85, 159) |
| HSL | hsl(213, 75%, 36%) |
| OKLCH | oklch(45.4% 0.135 255.8) |
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 #17559F | 7.40:1 | AAA | Lc -90.1 | Preferred for body text |
| Black text on #17559F | 2.83:1 | Fails | Lc 18.8 | Dividers and decoration only |
| #17559F text on white | 7.40:1 | AAA | Lc 85.2 | Fine for body text |
| #17559F text on black | 2.83:1 | Fails | Lc -16.8 | Dividers and decoration only |
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 800.
-
Step 50
50
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E0EBF9
oklch(93.6% 0.022 254.4)
-
Step 200
200
#C7DBF6
oklch(88.5% 0.043 255.9)
-
Step 300
300
#9FC3F3
oklch(80.8% 0.079 255.7)
-
Step 400
400
#6AA3EE
oklch(70.8% 0.126 255.7)
-
Step 500
500
#3E89E8
oklch(63% 0.161 255.8)
-
Step 600
600
#1771D7
oklch(55.7% 0.176 255.8)
-
Step 700
700
#065EBA
oklch(49.1% 0.163 255.8)
-
Step 800
800 (this color)
#17559F
oklch(45.4% 0.135 255.8)
-
Step 900
900
#154178
oklch(37.7% 0.105 256)
-
Step 950
950
#0E2646
oklch(26.9% 0.067 256.5)
#17559F 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) | #2D5CA2 | 0.028 |
| Deuteranopia (no green cones) | #08509E | 0.017 |
| Tritanopia (no blue cones) | #006772 | 0.102 |
| Achromatopsia (no color) | #555555 | 0.135 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #17559F
#17559F
oklch(45.4% 0.135 255.8)
- #744D00
#744D00
oklch(45.2% 0.095 75.5)
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 #17559F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.030
- Cobalt #1E488F ΔE 0.042
- Denim Blue #3B5B92 ΔE 0.044
- Light Navy #155084 ΔE 0.045
- Light Navy Blue #2E5A88 ΔE 0.046
- Deep Sea Blue #015482 ΔE 0.050
- Peacock Blue #016795 ΔE 0.057
- Dusky Blue #475F94 ΔE 0.061
Use #17559F 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.