Tailwind CSS v3 color

Tailwind sky-900 #0C4A6E

Tailwind CSS v3's sky-900 is #0C4A6E. It is a dark muted blue in the blue family. In OKLCH it sits at lightness 0.391, chroma 0.085 and hue 240.9°. The nearest CSS named color is darkslateblue (#483D8B), ΔE2000 14.6 away.

Relative luminance
0.0610
OKLCH L · C · h
0.391 · 0.085 · 240.9
Best text
White 9.45:1
Hue family
Blue
Inspect this color Check contrast

#0C4A6E color codes

HEX
#0C4A6E
RGB
rgb(12, 74, 110)
HSL
hsl(202, 80%, 24%)
OKLCH
oklch(0.391 0.085 240.9)
OKLab
oklab(0.391 -0.041 -0.074)
CIELAB (D65)
L* 29.67, a* -4.46, b* -26.01
XYZ (D65)
X 5.41, Y 6.10, Z 15.64
CMYK (naive)
cmyk(89%, 33%, 0%, 57%)

CIELAB and XYZ use the D65 white point; CSS lab() uses D50, so paste the OKLCH or HEX value into stylesheets. CMYK here is a plain formula with no press profile.

Legibility

Contrast: is #0C4A6E accessible?

White text on it reaches 9.45:1, passing AAA. Black text fails at 2.22:1.

WCAG 2 gives the same ratio whichever color is the text; APCA does not, so its Lc changes sign and size with polarity.

Open the Contrast System

  • Black text on it

    2.22:1

    • AA fails
    • AA large fails
    • AAA fails
    • APCA Lc +12

  • White text on it

    9.45:1

    • AA passes
    • AA large passes
    • AAA passes
    • APCA Lc −95

  • As text on black

    2.22:1

    • AA fails
    • AA large fails
    • AAA fails
    • APCA Lc −10

  • As text on white

    9.45:1

    • AA passes
    • AA large passes
    • AAA passes
    • APCA Lc +91

Nearest versions that pass 4.5:1

  • For text on white

    #0C4A6E 9.45:1

    It already reaches 9.45:1 on white, so no change is needed.

  • For text on black

    #437BA2 4.59:1

    Lightening its OKLCH lightness from 0.39 to 0.56 reaches 4.59:1 on black, keeping the hue.

    Compare both in the Contrast System

Checking another pair? Use the Contrast Checker.

Studio

Adjust #0C4A6E live

Move lightness, chroma and hue in OKLCH, or drag on the map. The map is every lightness and chroma at the current hue: sRGB inside the solid area, Display P3 out to the dashed line.

The studio needs JavaScript.

Scale

Shades and tints of #0C4A6E

Eleven OKLCH lightness steps at this hue, each with its contrast against white and black. #0C4A6E sits at step 800.

  1. 50#ECF7FF
    White
    1.08
    Black
    19.31
  2. 100#D9EFFF
    White
    1.18
    Black
    17.74
  3. 200#B2DEFF
    White
    1.42
    Black
    14.78
  4. 300#8FC5EC
    White
    1.84
    Black
    11.36
  5. 400#71A8D1
    White
    2.55
    Black
    8.22
  6. 500#558DB4
    White
    3.58
    Black
    5.85
  7. 600#3D759B
    White
    4.98
    Black
    4.21
  8. 700#275D81
    White
    7.07
    Black
    2.96
  9. 800This color#0C4A6E
    White
    9.45
    Black
    2.22
  10. 900#002C46
    White
    14.49
    Black
    1.44
  11. 950#001829
    White
    18.06
    Black
    1.16

Under each step, white and black text on it; a bold figure passes 4.5:1.

Tailwind CSS v3 sky scale

The real Tailwind palette, for comparison with the computed ramp above.

  1. 50#F0F9FF
    White
    1.06
    Black
    19.69
  2. 100#E0F2FE
    White
    1.14
    Black
    18.30
  3. 200#BAE6FD
    White
    1.32
    Black
    15.82
  4. 300#7DD3FC
    White
    1.66
    Black
    12.59
  5. 400#38BDF8
    White
    2.14
    Black
    9.80
  6. 500#0EA5E9
    White
    2.77
    Black
    7.57
  7. 600#0284C7
    White
    4.09
    Black
    5.12
  8. 700#0369A1
    White
    5.93
    Black
    3.53
  9. 800#075985
    White
    7.56
    Black
    2.77
  10. 900This color#0C4A6E
    White
    9.45
    Black
    2.22
  11. 950#082F49
    White
    13.87
    Black
    1.51

Gamut

How vivid #0C4A6E can get

At its lightness and hue, sRGB reaches OKLCH chroma 0.091; #0C4A6E uses 93% of it. Display P3, which many recent phones and laptops show, reaches 0.119 there: 31% more.

0.00.20.40.60.80.20.40.60.8 460480500520540560580600620
  • sRGB
  • Display P3
  • Rec. 2020
  • Dominant wavelength
OKLCH chroma
0.085
sRGB edge
0.091
Display P3 edge
0.119
Rec. 2020 edge
0.238
Dominant wavelength
479 nm
Excitation purity
52%
Chromaticity
x 0.1994, y 0.2247
  • This color#0C4A6E
  • Most vivid in sRGB#004A71
  • Most vivid in Display P3oklch(0.391 0.119 240.9)

On a screen without Display P3 the last tile shows the sRGB edge instead.

Use the wider color where screens show it
.accent {
  color: #0c4a6e;
}
@media (color-gamut: p3) {
  .accent { color: color(display-p3 0 0.2845 0.4784); }
}

Mixing

Mixing #0C4A6E

Each row is the same mix worked out in a different space, with the halfway color at its end. sRGB, which older CSS gradients use, can sag gray or dark in the middle; OKLab keeps the lightness steps even; OKLCH holds chroma and hue as it goes.

White #FFFFFF

  • sRGB50%#86A5B7
  • OKLab50%#86A1B5
  • OKLCH50%#86A1B5

Black #000000

  • sRGB50%#062537
  • OKLab50%#021726
  • OKLCH50%#021726

Its complement #65390A

  • sRGB50%#39423C
  • OKLab50%#454545
  • OKLCH50%#1C522D
In CSS
/* A gradient and a mix, worked out in OKLCH */
background: linear-gradient(in oklch, #0c4a6e, white);
color: color-mix(in oklch, #0c4a6e 50%, white);

In use

#0C4A6E in an interface

A button, a link, a heading, a focused field, an icon and a chart line in this color, on a light page and a dark one. Each check is a WCAG 2 contrast minimum: 1.4.3 for text, 1.4.11 for the rest.

Light page

  • Button labelText, 4.5:19.45:1 Passes
  • Link and body-size textText, 4.5:19.45:1 Passes
  • Large headingLarge text, 3:19.45:1 Passes
  • Icons, borders and focus ringsNon-text, 3:19.45:1 Passes

Dark page

  • Button labelText, 4.5:19.45:1 Passes
  • Link and body-size textText, 4.5:11.98:1 Fails
  • Large headingLarge text, 3:11.98:1 Fails
  • Icons, borders and focus ringsNon-text, 3:11.98:1 Fails

For text on this page, the nearest shade that passes is #4B82AA 4.52:1

Color vision

How #0C4A6E looks with color blindness

Achromatopsia changes it most, ΔE2000 16.7; deuteranopia changes it least, 8.2.

Simulated with Machado et al. (2009) at full severity, in linear light.

Simulate a whole page What each type sees

  • Protanopia

    No working red (long-wavelength) cones

    #394B70 ΔE2000 8.6

    Noticeable

    Reads as dark muted blue

  • Deuteranopia

    No working green (medium-wavelength) cones

    #2C426D ΔE2000 8.2

    Noticeable

    Reads as dark muted blue

  • Tritanopia

    No working blue (short-wavelength) cones

    #005357 ΔE2000 15.7

    Distinct

    Reads as dark muted teal

  • Achromatopsia

    No cone color vision; lightness only

    #464646 ΔE2000 16.7

    Distinct

    Reads as dark gray

Pairing check

Checked against its complement, #65390A. Their lightness contrast is only 1.03:1, so where hue collapses, add a label, icon or pattern.

VisionThe pairΔE2000Verdict
Normal vision#0C4A6E · #65390A37.5Stays distinct
Protanopia#394B70 · #473D0238.1Stays distinct
Deuteranopia#2C426D · #51480A40.8Stays distinct
Tritanopia#005357 · #6F2F3041.0Stays distinct
Achromatopsia#464646 · #4444440.7Easily confused

Harmony

Color harmonies for #0C4A6E

Its complement is #65390A, a dark muted brown, on the warm side of the wheel.

Hue rotations in OKLCH, mapped into sRGB by trimming chroma so hue and lightness stay put.

Open the Harmony Studio
  • Base#0C4A6E
  • Complement#65390A

Complementary

Open in Harmony Studio
  • −30°#004F5A
  • Base#0C4A6E
  • +30°#354272

Analogous

Open in Harmony Studio
  • Base#0C4A6E
  • +120°#693043
  • +240°#3F4C0E

Triadic

Open in Harmony Studio
  • Base#0C4A6E
  • +150°#6B3228
  • +210°#554300

Split-complementary

Open in Harmony Studio

Code

Design tokens

Ready-to-paste tokens in six formats. Rename them to fit your system.

CSS custom property

:root {
  --color-sky-900: #0c4a6e;
}

Tailwind config

// tailwind.config.js — already built in as sky-900;
// pin the v3 value explicitly like this:
module.exports = {
  theme: {
    extend: {
      colors: {
        sky: { 900: '#0c4a6e' },
      },
    },
  },
};

Tailwind v4 theme

/* app.css — Tailwind CSS v4 */
@import "tailwindcss";

@theme {
  /* v4 has its own sky-900; this pins the v3 value. */
  --color-sky-900: oklch(0.391 0.085 240.9);
}

Design token (W3C DTCG)

{
  "color": {
    "sky-900": {
      "$type": "color",
      "$value": {
        "colorSpace": "srgb",
        "components": [0.0471, 0.2902, 0.4314],
        "hex": "#0c4a6e"
      },
      "$description": "Tailwind CSS v3 sky-900"
    }
  }
}

SwiftUI color

import SwiftUI

enum Palette {
    static let sky900 = Color(.sRGB, red: 0.047, green: 0.290, blue: 0.431, opacity: 1)
}

Jetpack Compose color

import androidx.compose.ui.graphics.Color

object Palette {
    val Sky900 = Color(0xFF0C4A6E)
}

Matches

The nearest match in each system

The closest CSS name, Tailwind shade, RAL Classic paint and Crayola crayon by ΔE2000; under 2 is hard to tell apart side by side. RAL and Crayola values approximate physical colors.

Neighbors

The eight nearest colors on this site by ΔE2000, closest first. Under 2 is hard to tell apart side by side.

Tools

Open #0C4A6E in the tools

Each opens over this page. More colors live in the Color Library, and every color page is listed on the hub.