#15537C
Closest named color: Deep Sea Blue (#015482). oklch(42.5% 0.091 243), rgb(21, 83, 124).
Aa
White text reads best on this color (8.20:1).
About this color
#15537C is a dark, moderately saturated blue. In OKLCH its lightness is 43%, its chroma 0.091 and its hue 243°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Sea Blue (#015482), ΔE 0.011 away. White text reads best on it, at 8.20:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.091) |
| Temperature | cool |
| Nearest name | Deep Sea Blue (#015482) |
| Black text | 2.56:1 |
| White text | 8.20:1 |
Values
| HEX | #15537C |
| RGB | rgb(21, 83, 124) |
| HSL | hsl(204, 71%, 28%) |
| OKLCH | oklch(42.5% 0.091 243) |
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 #15537C | 8.20:1 | AAA | Lc -92.7 | Preferred for body text |
| Black text on #15537C | 2.56:1 | Fails | Lc 16.0 | Dividers and decoration only |
| #15537C text on white | 8.20:1 | AAA | Lc 88.0 | Fine for body text |
| #15537C text on black | 2.56:1 | Fails | Lc -14.2 | 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
#F1F6FA
oklch(97.1% 0.008 241.7)
-
Step 100
100
#E1EBF4
oklch(93.5% 0.016 245.1)
-
Step 200
200
#C9DCEC
oklch(88.5% 0.03 243.4)
-
Step 300
300
#A4C5E1
oklch(80.9% 0.053 244.1)
-
Step 400
400
#71A7D2
oklch(70.7% 0.085 243.4)
-
Step 500
500
#4890C6
oklch(63% 0.109 243.5)
-
Step 600
600
#247AB3
oklch(55.7% 0.119 242.9)
-
Step 700
700
#15669A
oklch(49.1% 0.111 243.4)
-
Step 800
800 (this color)
#15537C
oklch(42.5% 0.091 243)
-
Step 900
900
#1A4564
oklch(37.6% 0.071 243.3)
-
Step 950
950
#11293B
oklch(27.1% 0.045 243.2)
#15537C 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) | #40547E | 0.042 |
| Deuteranopia (no green cones) | #314B7B | 0.031 |
| Tritanopia (no blue cones) | #005D62 | 0.062 |
| Achromatopsia (no color) | #4F4F4F | 0.091 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #15537C
#15537C
oklch(42.5% 0.091 243)
- #71420B
#71420B
oklch(42.6% 0.091 63.3)
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 #15537C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Sea Blue #015482 ΔE 0.011
- Light Navy #155084 ΔE 0.018
- Dusk Blue #26538D ΔE 0.032
- Light Navy Blue #2E5A88 ΔE 0.036
- Cobalt #1E488F ΔE 0.049
- Twilight Blue #0A437A ΔE 0.050
- YInMn Blue #415A77 ΔE 0.051
- Petrol #005F6A ΔE 0.055
Use #15537C 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.