#17537B
Closest named color: Deep Sea Blue (#015482). oklch(42.5% 0.089 242.8), rgb(23, 83, 123).
Aa
White text reads best on this color (8.20:1).
About this color
#17537B is a dark, moderately saturated blue. In OKLCH its lightness is 43%, its chroma 0.089 and its hue 243°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Sea Blue (#015482), ΔE 0.013 away. White text reads best on it, at 8.20:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.089) |
| Temperature | cool |
| Nearest name | Deep Sea Blue (#015482) |
| Black text | 2.55:1 |
| White text | 8.20:1 |
Values
| HEX | #17537B |
| RGB | rgb(23, 83, 123) |
| HSL | hsl(204, 68%, 29%) |
| OKLCH | oklch(42.5% 0.089 242.8) |
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 #17537B | 8.20:1 | AAA | Lc -92.7 | Preferred for body text |
| Black text on #17537B | 2.55:1 | Fails | Lc 16.0 | Dividers and decoration only |
| #17537B text on white | 8.20:1 | AAA | Lc 88.0 | Fine for body text |
| #17537B text on black | 2.55:1 | Fails | Lc -14.1 | 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 800.
-
Step 50
50
#F2F6FA
oklch(97.1% 0.007 247.9)
-
Step 100
100
#E2EBF3
oklch(93.6% 0.015 244.7)
-
Step 200
200
#C9DCEB
oklch(88.5% 0.029 241.6)
-
Step 300
300
#A4C5E0
oklch(80.8% 0.052 243.1)
-
Step 400
400
#72A7D1
oklch(70.7% 0.083 243.2)
-
Step 500
500
#4990C5
oklch(63% 0.107 243.3)
-
Step 600
600
#277AB1
oklch(55.7% 0.115 242.5)
-
Step 700
700
#186698
oklch(49% 0.107 242.8)
-
Step 800
800 (this color)
#17537B
oklch(42.5% 0.089 242.8)
-
Step 900
900
#1B4563
oklch(37.6% 0.069 242.8)
-
Step 950
950
#11293A
oklch(27% 0.044 241.7)
#17537B 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) | #40547D | 0.041 |
| Deuteranopia (no green cones) | #324B7A | 0.031 |
| Tritanopia (no blue cones) | #005D61 | 0.062 |
| Achromatopsia (no color) | #4F4F4F | 0.089 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #17537B
#17537B
oklch(42.5% 0.089 242.8)
- #70420E
#70420E
oklch(42.5% 0.089 63.1)
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 #17537B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Sea Blue #015482 ΔE 0.013
- Light Navy #155084 ΔE 0.019
- Dusk Blue #26538D ΔE 0.033
- Light Navy Blue #2E5A88 ΔE 0.036
- YInMn Blue #415A77 ΔE 0.049
- Cobalt #1E488F ΔE 0.051
- Twilight Blue #0A437A ΔE 0.051
- Petrol #005F6A ΔE 0.054
Use #17537B 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.