CSS named color

Medium Aquamarine #66CDAA

The CSS keyword mediumaquamarine is #66CDAA. It is a light soft green in the green family. In OKLCH it sits at lightness 0.777, chroma 0.110 and hue 168.8°.

Relative luminance
0.4939
OKLCH L · C · h
0.777 · 0.110 · 168.8
Best text
Black 10.87:1
Hue family
Green

#66CDAA color codes

HEX
#66CDAA
RGB
rgb(102, 205, 170)
HSL
hsl(160, 51%, 60%)
OKLCH
oklch(0.777 0.110 168.8)
OKLab
oklab(0.777 -0.108 0.021)
CIELAB (D65)
L* 75.69, a* -38.34, b* 8.31
XYZ (D65)
X 34.56, Y 49.39, Z 45.73
CMYK (naive)
cmyk(50%, 0%, 17%, 20%)

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 #66CDAA accessible?

Black text on it reaches 10.87:1, passing AAA. White text fails at 1.93:1.

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

    10.87:1

    • AA passes
    • AA large passes
    • AAA passes
    • APCA Lc +67
  • White text on it

    1.93:1

    • AA fails
    • AA large fails
    • AAA fails
    • APCA Lc −41
  • As text on black

    10.87:1

    • AA passes
    • AA large passes
    • AAA passes
    • APCA Lc −65
  • As text on white

    1.93:1

    • AA fails
    • AA large fails
    • AAA fails
    • APCA Lc +36

Nearest versions that pass 4.5:1

  • For text on white

    #048667 4.55:1

    Darkening its OKLCH lightness from 0.78 to 0.55 reaches 4.55:1 on white, keeping the hue.

  • For text on black

    #66CDAA 10.87:1

    It already reaches 10.87:1 on black, so no change is needed.

Checking another pair? Use the Contrast Checker.

Studio

Adjust #66CDAA 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 #66CDAA

Eleven OKLCH lightness steps at this hue, each with its contrast against white and black. #66CDAA sits at step 300.

  1. 50#DAFFF0
    White
    1.07
    Black
    19.54
  2. 100#AFFFE1
    White
    1.15
    Black
    18.21
  3. 200#95EDCC
    White
    1.37
    Black
    15.26
  4. 300This color#66CDAA
    White
    1.93
    Black
    10.87
  5. 400#52B796
    White
    2.44
    Black
    8.57
  6. 500#2D9B7A
    White
    3.45
    Black
    6.08
  7. 600#008263
    White
    4.80
    Black
    4.37
  8. 700#00684F
    White
    6.78
    Black
    3.09
  9. 800#004C39
    White
    10.03
    Black
    2.09
  10. 900#003224
    White
    14.17
    Black
    1.48
  11. 950#001C13
    White
    17.86
    Black
    1.17

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

Gamut

How vivid #66CDAA can get

At its lightness and hue, sRGB reaches OKLCH chroma 0.156; #66CDAA uses 70% of it. Display P3, which many recent phones and laptops show, reaches 0.213 there: 37% more.

0.00.20.40.60.80.20.40.60.8 460480500520540560580600620
  • sRGB
  • Display P3
  • Rec. 2020
  • Dominant wavelength
OKLCH chroma
0.110
sRGB edge
0.156
Display P3 edge
0.213
Rec. 2020 edge
0.336
Dominant wavelength
506 nm
Excitation purity
15%
Chromaticity
x 0.2665, y 0.3808
  • This color#66CDAA
  • Most vivid in sRGB#00D5A5
  • Most vivid in Display P3oklch(0.777 0.213 168.8)

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

Use the wider color where screens show it
.accent {
  color: #66cdaa;
}
@media (color-gamut: p3) {
  .accent { color: color(display-p3 0 0.8581 0.6354); }
}

Mixing

Mixing #66CDAA

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%#B3E6D5
  • OKLab50%#B8E7D4
  • OKLCH50%#B8E7D4

Black #000000

  • sRGB50%#336755
  • OKLab50%#234E3F
  • OKLCH50%#234E3F

Its complement #EB99C2

  • sRGB50%#A9B3B6
  • OKLab50%#B6B6B6
  • OKLCH50%#8BB8FC
In CSS
/* A gradient and a mix, worked out in OKLCH */
background: linear-gradient(in oklch, #66cdaa, white);
color: color-mix(in oklch, #66cdaa 50%, white);

In use

#66CDAA 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, 4.5:110.87:1 Passes
  • Link and body-size textText, 4.5:11.93:1 Fails
  • Large headingLarge text, 3:11.93:1 Fails
  • Icons, borders and focus ringsNon-text, 3:11.93:1 Fails

For text on this page, the nearest shade that passes is #048667 4.55:1

Dark page

  • Button labelText, 4.5:110.87:1 Passes
  • Link and body-size textText, 4.5:19.70:1 Passes
  • Large headingLarge text, 3:19.70:1 Passes
  • Icons, borders and focus ringsNon-text, 3:19.70:1 Passes

Color vision

How #66CDAA looks with color blindness

Achromatopsia changes it most, ΔE2000 23.7; tritanopia changes it least, 8.7.

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

    #C8C1A8 ΔE2000 22.3

    Distinct

    Reads as light grayish amber

  • Deuteranopia

    No working green (medium-wavelength) cones

    #B9B6AC ΔE2000 22.7

    Distinct

    Reads as light gray

  • Tritanopia

    No working blue (short-wavelength) cones

    #3ECEC3 ΔE2000 8.7

    Noticeable

    Reads as light soft cyan

  • Achromatopsia

    No cone color vision; lightness only

    #BABABA ΔE2000 23.7

    Distinct

    Reads as light gray

Pairing check

Checked against its complement, #EB99C2. Their lightness contrast is only 1.10:1, so where hue collapses, add a label, icon or pattern.

VisionThe pairΔE2000Verdict
Normal vision#66CDAA · #EB99C247.0Stays distinct
Protanopia#C8C1A8 · #A0A9C424.2Stays distinct
Deuteranopia#B9B6AC · #B4B7C09.7Harder to tell apart
Tritanopia#3ECEC3 · #F697A755.8Stays distinct
Achromatopsia#BABABA · #B2B2B22.2Easily confused

Harmony

Color harmonies for #66CDAA

Its complement is #EB99C2, a light soft pink, 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#66CDAA
  • Complement#EB99C2

Complementary

Open in Harmony Studio
  • −30°#92C783
  • Base#66CDAA
  • +30°#4DCCD1
  • Base#66CDAA
  • +120°#B4ABF8
  • +240°#F0A177
  • Base#66CDAA
  • +150°#D5A0E3
  • +210°#F4999B

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-mediumaquamarine: #66cdaa;
}

Tailwind config

// tailwind.config.js
module.exports = {
  theme: {
    extend: {
      colors: {
        mediumaquamarine: '#66cdaa',
      },
    },
  },
};

Tailwind v4 theme

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

@theme {
  --color-mediumaquamarine: oklch(0.777 0.110 168.8);
}

Design token (W3C DTCG)

{
  "color": {
    "mediumaquamarine": {
      "$type": "color",
      "$value": {
        "colorSpace": "srgb",
        "components": [0.4, 0.8039, 0.6667],
        "hex": "#66cdaa"
      },
      "$description": "CSS named color mediumaquamarine"
    }
  }
}

SwiftUI color

import SwiftUI

enum Palette {
    static let mediumaquamarine = Color(.sRGB, red: 0.400, green: 0.804, blue: 0.667, opacity: 1)
}

Jetpack Compose color

import androidx.compose.ui.graphics.Color

object Palette {
    val Mediumaquamarine = Color(0xFF66CDAA)
}

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.

Tools

Open #66CDAA in the tools

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