OKLCH to HEX: #64748B

Also known as: Tailwind v3 slate-500

oklch(0.55439 0.04072 257.417) → #64748B

Values are shown at full precision, so converting back gives exactly #64748b. 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. input
```
oklch(0.55439 0.04072 257.417)
```

2. OKLCH → Oklab

a = C·cos H = -0.00887
b = C·sin H = -0.03974

3. Oklab → LMS′

l′ = L + 0.3963·a + 0.2158·b = 0.542298
m′ = L − 0.1056·a − 0.0639·b = 0.557864
s′ = L − 0.0895·a − 1.2915·b = 0.606510

4. cube

l = 0.542298³ = 0.159483
m = 0.557864³ = 0.173614
s = 0.606510³ = 0.223107

5. LMS → linear sRGB

R = 4.0767·l − 3.3077·m + 0.2310·s = 0.127434
G = −1.2684·l + 2.6098·m − 0.3413·s = 0.174646
B = −0.0042·l − 0.7034·m + 1.7076·s = 0.258189

6. linear → sRGB, × 255

R = 0.39215 × 255 = 100.00 → 100
G = 0.45490 × 255 = 116.00 → 116
B = 0.54510 × 255 = 139.00 → 139

7. RGB → HEX
```
#64748B
```

All formats

HEX: #64748b
RGB: rgb(100 116 139)
RGB (legacy): rgb(100, 116, 139)
HSL: hsl(215.38 16.32% 46.86%) → hsl(215 16% 47%)
HWB: hwb(215 39% 45%)
OKLCH: oklch(0.554 0.041 257.4) · oklch(55.4% 0.041 257.4)
OKLab: oklab(0.554 -0.009 -0.040)
Lab (D50): lab(48.16 -1.93 -14.72)
LCH (D50): lch(48.16 14.85 262.54)
Display P3: color(display-p3 0.4042 0.4530 0.5370)
Linear sRGB: color(srgb-linear 0.1274 0.1746 0.2582)

Gamut: sRGB and Display P3

#64748B is a hex color, so it sits inside sRGB and therefore inside Display P3. At this lightness and hue, sRGB reaches chroma 0.200 and Display P3 reaches 0.254; this color uses 20% of the sRGB chroma available.

CSS snippets

.element {
  color: #64748b;
  color: rgb(100 116 139);
  color: hsl(215 16% 47%);
  color: oklch(0.554 0.041 257.4);
}

/* Tailwind CSS v4 */
@theme {
  --color-brand: oklch(0.554 0.041 257.4);
}
/* arbitrary values */
class="text-[#64748b] bg-[oklch(0.554_0.041_257.4)]"

/* wide-gamut screens */
@media (color-gamut: p3) {
  .element { color: color(display-p3 0.4042 0.4530 0.5370); }
}

/* relative color syntax: 10% darker */
.element-dark { color: oklch(from #64748b 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

#75869D · oklch(0.614 0.041 257.4) · ΔL +0.06
#536379 · oklch(0.494 0.041 257.4) · 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?