#18578E
Closest named color: Dusk Blue (#26538D). oklch(44.7% 0.109 249.5), rgb(24, 87, 142).
Aa
White text reads best on this color (7.51:1).
About this color
#18578E is a dark, moderately saturated blue. In OKLCH its lightness is 45%, its chroma 0.109 and its hue 249°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.014 away. White text reads best on it, at 7.51:1.
| Hue family | Blues |
| Lightness | dark (45%) |
| Chroma | moderately saturated (0.109) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 2.79:1 |
| White text | 7.51:1 |
Values
| HEX | #18578E |
| RGB | rgb(24, 87, 142) |
| HSL | hsl(208, 71%, 33%) |
| OKLCH | oklch(44.7% 0.109 249.5) |
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 #18578E | 7.51:1 | AAA | Lc -90.6 | Preferred for body text |
| Black text on #18578E | 2.79:1 | Fails | Lc 18.3 | Dividers and decoration only |
| #18578E text on white | 7.51:1 | AAA | Lc 85.7 | Fine for body text |
| #18578E text on black | 2.79:1 | Fails | Lc -16.3 | 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
#F1F6FB
oklch(97.1% 0.009 247.9)
-
Step 100
100
#E1EBF6
oklch(93.6% 0.018 250.6)
-
Step 200
200
#C8DCF0
oklch(88.6% 0.035 248.2)
-
Step 300
300
#A1C5E9
oklch(81% 0.064 248.6)
-
Step 400
400
#6DA5DE
oklch(70.6% 0.103 249.9)
-
Step 500
500
#438ED5
oklch(63.2% 0.131 249.6)
-
Step 600
600
#1C76C2
oklch(55.5% 0.143 249.6)
-
Step 700
700
#0B63A8
oklch(49.1% 0.133 249.7)
-
Step 800
800 (this color)
#18578E
oklch(44.7% 0.109 249.5)
-
Step 900
900
#17446D
oklch(37.8% 0.086 249.5)
-
Step 950
950
#0F2840
oklch(27% 0.055 249.7)
#18578E 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) | #3D5A90 | 0.036 |
| Deuteranopia (no green cones) | #2B508D | 0.022 |
| Tritanopia (no blue cones) | #00646B | 0.080 |
| Achromatopsia (no color) | #545454 | 0.109 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #18578E
#18578E
oklch(44.7% 0.109 249.5)
- #764900
#764900
oklch(44.7% 0.097 69.8)
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 #18578E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.014
- Light Navy Blue #2E5A88 ΔE 0.023
- Deep Sea Blue #015482 ΔE 0.024
- Light Navy #155084 ΔE 0.025
- Denim Blue #3B5B92 ΔE 0.035
- Cobalt #1E488F ΔE 0.043
- Peacock Blue #016795 ΔE 0.046
- Denim #3B638C ΔE 0.051
Use #18578E 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.