HEX to HSL: #312C85

Also known as: Tailwind indigo-900

#312C85 → hsl(243 50% 35%)

Values are shown at full precision, so converting back gives exactly #312c85. The rounded form is what you normally paste into CSS.

Step-by-step math

Every number below is computed from the input, nothing is looked up.

1. RGB ÷ 255
```
R = 0.1922
G = 0.1725
B = 0.5216
```

2. max, min, Δ

max = 0.5216
min = 0.1725
Δ = max − min = 0.3490

3. L
```
L = (max + min) / 2 = 0.3471 = 34.71%
```

4. S

S = Δ / (1 − |2L − 1|) = 0.5028 = 50.28%

5. H

max is B → H = 60° × ((R − G) / Δ + 4) = 60° × ((0.1922 − 0.1725) / 0.3490 + 4) = 243.37°

6. HSL
```
hsl(243.37 50.28% 34.71%)
```

All formats

HEX: #312c85
RGB: rgb(49 44 133)
RGB (legacy): rgb(49, 44, 133)
HSL: hsl(243.37 50.28% 34.71%) → hsl(243 50% 35%)
HWB: hwb(243 17% 48%)
OKLCH: oklch(0.359 0.144 278.8) · oklch(35.9% 0.144 278.8)
OKLab: oklab(0.359 0.022 -0.142)
Lab (D50): lab(23.37 24.66 -50.32)
LCH (D50): lch(23.37 56.04 296.10)
Display P3: color(display-p3 0.1888 0.1732 0.5020)
Linear sRGB: color(srgb-linear 0.0307 0.0252 0.2346)

Gamut: sRGB and Display P3

#312C85 is a hex color, so it sits inside sRGB and therefore inside Display P3. At this lightness and hue, sRGB reaches chroma 0.219 and Display P3 reaches 0.222; this color uses 66% of the sRGB chroma available.

CSS snippets

.element {
  color: #312c85;
  color: rgb(49 44 133);
  color: hsl(243 50% 35%);
  color: oklch(0.359 0.144 278.8);
}

/* Tailwind CSS v4 */
@theme {
  --color-brand: oklch(0.359 0.144 278.8);
}
/* arbitrary values */
class="text-[#312c85] bg-[oklch(0.359_0.144_278.8)]"

/* wide-gamut screens */
@media (color-gamut: p3) {
  .element { color: color(display-p3 0.1888 0.1732 0.5020); }
}

/* relative color syntax: 10% darker */
.element-dark { color: oklch(from #312c85 calc(l - 0.1) c h); }

Nearby colors

Closest colors in the Tailwind and CSS named palettes (OKLab distance).

Lighter and darker, same hue and chroma

#3F3E98 · oklch(0.419 0.144 278.8) · ΔL +0.06
#241972 · oklch(0.299 0.144 278.8) · ΔL −0.06

Open in the studio

Open in the OKLCH picker Check contrast on white

Other converters for this color

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Guides: What is OKLCH?