Tailwind CSS v3 color

Tailwind blue-600 #2563EB

Tailwind CSS v3's blue-600 is #2563EB. It is a vivid blue in the blue family. In OKLCH it sits at lightness 0.546, chroma 0.215 and hue 262.9°. The nearest CSS named color is royalblue (#4169E1), ΔE2000 2.5 away.

Relative luminance
0.1532
OKLCH L · C · h
0.546 · 0.215 · 262.9
Best text
White 5.16:1
Hue family
Blue
Inspect this color Check contrast

#2563EB color codes

HEX
#2563EB
RGB
rgb(37, 99, 235)
HSL
hsl(221, 83%, 53%)
OKLCH
oklch(0.546 0.215 262.9)
OKLab
oklab(0.546 -0.027 -0.214)
CIELAB (D65)
L* 46.06, a* 30.96, b* -73.83
XYZ (D65)
X 20.21, Y 15.31, Z 80.47
CMYK (naive)
cmyk(84%, 58%, 0%, 8%)

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 #2563EB accessible?

White text on it reaches 5.16:1, passing AA. Black text manages only 4.06:1, enough for large text only.

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

    4.06:1

    • AA fails
    • AA large passes
    • AAA fails
    • APCA Lc +29

  • White text on it

    5.16:1

    • AA passes
    • AA large passes
    • AAA fails
    • APCA Lc −80

  • As text on black

    4.06:1

    • AA fails
    • AA large passes
    • AAA fails
    • APCA Lc −26

  • As text on white

    5.16:1

    • AA passes
    • AA large passes
    • AAA fails
    • APCA Lc +74

Nearest versions that pass 4.5:1

  • For text on white

    #2563EB 5.16:1

    It already reaches 5.16:1 on white, so no change is needed.

  • For text on black

    #2C6BF4 4.51:1

    Lightening its OKLCH lightness from 0.55 to 0.57 reaches 4.51:1 on black, keeping the hue.

    Compare both in the Contrast System

Checking another pair? Use the Contrast Checker.

Studio

Adjust #2563EB 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 #2563EB

Eleven OKLCH lightness steps at this hue, each with its contrast against white and black. #2563EB sits at step 600.

  1. 50#F0F5FF
    White
    1.09
    Black
    19.21
  2. 100#E1ECFF
    White
    1.19
    Black
    17.64
  3. 200#C3D8FF
    White
    1.43
    Black
    14.58
  4. 300#9BBEFF
    White
    1.87
    Black
    11.20
  5. 400#6E9FFF
    White
    2.60
    Black
    8.06
  6. 500#3F7DFF
    White
    3.75
    Black
    5.58
  7. 600This color#2563EB
    White
    5.16
    Black
    4.06
  8. 700#0D48CA
    White
    7.50
    Black
    2.79
  9. 800#002F9F
    White
    11.01
    Black
    1.90
  10. 900#001D6C
    White
    15.08
    Black
    1.39
  11. 950#000E43
    White
    18.35
    Black
    1.14

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

Tailwind CSS v3 blue scale

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

  1. 50#EFF6FF
    White
    1.08
    Black
    19.29
  2. 100#DBEAFE
    White
    1.22
    Black
    17.21
  3. 200#BFDBFE
    White
    1.42
    Black
    14.77
  4. 300#93C5FD
    White
    1.80
    Black
    11.64
  5. 400#60A5FA
    White
    2.54
    Black
    8.25
  6. 500#3B82F6
    White
    3.67
    Black
    5.70
  7. 600This color#2563EB
    White
    5.16
    Black
    4.06
  8. 700#1D4ED8
    White
    6.70
    Black
    3.13
  9. 800#1E40AF
    White
    8.72
    Black
    2.40
  10. 900#1E3A8A
    White
    10.35
    Black
    2.02
  11. 950#172554
    White
    14.69
    Black
    1.42

Gamut

How vivid #2563EB can get

At its lightness and hue, sRGB reaches OKLCH chroma 0.251; #2563EB uses 86% of it. Display P3, which many recent phones and laptops show, reaches 0.269 there: 7% more.

0.00.20.40.60.80.20.40.60.8 460480500520540560580600620
  • sRGB
  • Display P3
  • Rec. 2020
  • Dominant wavelength
OKLCH chroma
0.215
sRGB edge
0.251
Display P3 edge
0.269
Rec. 2020 edge
0.272
Dominant wavelength
470 nm
Excitation purity
73%
Chromaticity
x 0.1743, y 0.1320
  • This color#2563EB
  • Most vivid in sRGB#115CFF
  • Most vivid in Display P3oklch(0.546 0.269 262.9)

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

Use the wider color where screens show it
.accent {
  color: #2563eb;
}
@media (color-gamut: p3) {
  .accent { color: color(display-p3 0.1405 0.3352 1); }
}

Mixing

Mixing #2563EB

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%#92B1F5
  • OKLab50%#91B5FA
  • OKLCH50%#91B5FA

Black #000000

  • sRGB50%#133276
  • OKLab50%#08215B
  • OKLCH50%#08215B

Its complement #906900

  • sRGB50%#5B6676
  • OKLab50%#61718F
  • OKLCH50%#B43D79
In CSS
/* A gradient and a mix, worked out in OKLCH */
background: linear-gradient(in oklch, #2563eb, white);
color: color-mix(in oklch, #2563eb 50%, white);

In use

#2563EB 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, 4.5:15.16:1 Passes
  • Link and body-size textText, 4.5:15.16:1 Passes
  • Large headingLarge text, 3:15.16:1 Passes
  • Icons, borders and focus ringsNon-text, 3:15.16:1 Passes

Dark page

  • Button labelText, 4.5:15.16:1 Passes
  • Link and body-size textText, 4.5:13.62:1 Fails
  • Large headingLarge text, 3:13.62:1 Passes
  • Icons, borders and focus ringsNon-text, 3:13.62:1 Passes

For text on this page, the nearest shade that passes is #3575FE 4.57:1

Color vision

How #2563EB looks with color blindness

Achromatopsia changes it most, ΔE2000 28.6; deuteranopia changes it least, 1.8.

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

    #0076F0 ΔE2000 7.3

    Noticeable

    Reads as vivid blue

  • Deuteranopia

    No working green (medium-wavelength) cones

    #0064E8 ΔE2000 1.8

    Very close

    Reads as vivid blue

  • Tritanopia

    No working blue (short-wavelength) cones

    #00869D ΔE2000 23.8

    Distinct

    Reads as soft blue

  • Achromatopsia

    No cone color vision; lightness only

    #6D6D6D ΔE2000 28.6

    Distinct

    Reads as gray

Pairing check

Checked against its complement, #906900. Their lightness contrast is only 1.03:1, so where hue collapses, add a label, icon or pattern.

VisionThe pairΔE2000Verdict
Normal vision#2563EB · #90690058.2Stays distinct
Protanopia#0076F0 · #796A0059.4Stays distinct
Deuteranopia#0064E8 · #82740962.2Stays distinct
Tritanopia#00869D · #9D5D5949.3Stays distinct
Achromatopsia#6D6D6D · #6F6F6F0.8Easily confused

Harmony

Color harmonies for #2563EB

Its complement is #906900, a soft 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#2563EB
  • Complement#906900

Complementary

Open in Harmony Studio
  • −30°#007AA7
  • Base#2563EB
  • +30°#7A49DF

Analogous

Open in Harmony Studio
  • Base#2563EB
  • +120°#D10E2E
  • +240°#008908

Triadic

Open in Harmony Studio
  • Base#2563EB
  • +150°#AD5400
  • +210°#727700

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-blue-600: #2563eb;
}

Tailwind config

// tailwind.config.js — already built in as blue-600;
// pin the v3 value explicitly like this:
module.exports = {
  theme: {
    extend: {
      colors: {
        blue: { 600: '#2563eb' },
      },
    },
  },
};

Tailwind v4 theme

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

@theme {
  /* v4 has its own blue-600; this pins the v3 value. */
  --color-blue-600: oklch(0.546 0.215 262.9);
}

Design token (W3C DTCG)

{
  "color": {
    "blue-600": {
      "$type": "color",
      "$value": {
        "colorSpace": "srgb",
        "components": [0.1451, 0.3882, 0.9216],
        "hex": "#2563eb"
      },
      "$description": "Tailwind CSS v3 blue-600"
    }
  }
}

SwiftUI color

import SwiftUI

enum Palette {
    static let blue600 = Color(.sRGB, red: 0.145, green: 0.388, blue: 0.922, opacity: 1)
}

Jetpack Compose color

import androidx.compose.ui.graphics.Color

object Palette {
    val Blue600 = Color(0xFF2563EB)
}

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 #2563EB in the tools

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