#18588B
Closest named color: Dusk Blue (#26538D). oklch(44.8% 0.104 247.4), rgb(24, 88, 139).
Aa
White text reads best on this color (7.47:1).
About this color
#18588B is a dark, moderately saturated blue. In OKLCH its lightness is 45%, its chroma 0.104 and its hue 247°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.017 away. White text reads best on it, at 7.47:1.
| Hue family | Blues |
| Lightness | dark (45%) |
| Chroma | moderately saturated (0.104) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 2.80:1 |
| White text | 7.47:1 |
Values
| HEX | #18588B |
| RGB | rgb(24, 88, 139) |
| HSL | hsl(207, 71%, 32%) |
| OKLCH | oklch(44.8% 0.104 247.4) |
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 #18588B | 7.47:1 | AAA | Lc -90.5 | Preferred for body text |
| Black text on #18588B | 2.80:1 | Fails | Lc 18.4 | Dividers and decoration only |
| #18588B text on white | 7.47:1 | AAA | Lc 85.6 | Fine for body text |
| #18588B text on black | 2.80:1 | Fails | Lc -16.4 | 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
#E1EBF5
oklch(93.5% 0.017 248)
-
Step 200
200
#C8DCEF
oklch(88.5% 0.034 246.8)
-
Step 300
300
#A2C5E7
oklch(80.9% 0.061 247.8)
-
Step 400
400
#6DA6DB
oklch(70.7% 0.098 247.6)
-
Step 500
500
#438FD1
oklch(63.2% 0.125 247.5)
-
Step 600
600
#1C78BE
oklch(55.7% 0.136 247.3)
-
Step 700
700
#0A64A4
oklch(49% 0.127 247.7)
-
Step 800
800 (this color)
#18588B
oklch(44.8% 0.104 247.4)
-
Step 900
900
#17446A
oklch(37.6% 0.081 247.7)
-
Step 950
950
#0F283E
oklch(26.9% 0.052 247.6)
#18588B 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) | #405A8D | 0.038 |
| Deuteranopia (no green cones) | #2F508A | 0.027 |
| Tritanopia (no blue cones) | #00646B | 0.074 |
| Achromatopsia (no color) | #555555 | 0.105 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #18588B
#18588B
oklch(44.8% 0.104 247.4)
- #784800
#784800
oklch(44.8% 0.099 67.4)
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 #18588B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.017
- Light Navy Blue #2E5A88 ΔE 0.019
- Deep Sea Blue #015482 ΔE 0.022
- Light Navy #155084 ΔE 0.025
- Denim Blue #3B5B92 ΔE 0.035
- Peacock Blue #016795 ΔE 0.044
- Cobalt #1E488F ΔE 0.048
- Denim #3B638C ΔE 0.048
Use #18588B 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.