RGB to HEX: #1C398E

Also known as: Tailwind blue-900

rgb(28 57 142) → #1C398E

Values are shown at full precision, so converting back gives exactly #1c398e. 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. base 10 → base 16

R = 28 = 1×16 + 12 → 1C
G = 57 = 3×16 + 9 → 39
B = 142 = 8×16 + 14 → 8E

2. pairs → HEX
```
1C 39 8E → #1C398E
```

All formats

HEX: #1c398e
RGB: rgb(28 57 142)
RGB (legacy): rgb(28, 57, 142)
HSL: hsl(224.74 67.06% 33.33%) → hsl(225 67% 33%)
HWB: hwb(225 11% 44%)
OKLCH: oklch(0.380 0.145 265.5) · oklch(38.0% 0.145 265.5)
OKLab: oklab(0.380 -0.011 -0.145)
Lab (D50): lab(26.25 15.50 -51.29)
LCH (D50): lch(26.25 53.58 286.81)
Display P3: color(display-p3 0.1373 0.2208 0.5366)
Linear sRGB: color(srgb-linear 0.0116 0.0409 0.2705)

Gamut: sRGB and Display P3

#1C398E is a hex color, so it sits inside sRGB and therefore inside Display P3. At this lightness and hue, sRGB reaches chroma 0.259 and Display P3 reaches 0.260; this color uses 56% of the sRGB chroma available.

CSS snippets

.element {
  color: #1c398e;
  color: rgb(28 57 142);
  color: hsl(225 67% 33%);
  color: oklch(0.380 0.145 265.5);
}

/* Tailwind CSS v4 */
@theme {
  --color-brand: oklch(0.380 0.145 265.5);
}
/* arbitrary values */
class="text-[#1c398e] bg-[oklch(0.380_0.145_265.5)]"

/* wide-gamut screens */
@media (color-gamut: p3) {
  .element { color: color(display-p3 0.1373 0.2208 0.5366); }
}

/* relative color syntax: 10% darker */
.element-dark { color: oklch(from #1c398e 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

#2B4BA1 · oklch(0.440 0.145 265.5) · ΔL +0.06
#0E277B · oklch(0.320 0.145 265.5) · ΔL −0.06

Open in the studio

Open in the OKLCH picker Check contrast on white

Other converters for this color

All converters →

Guides: What is OKLCH?