Color reference

#21525A color reference

Muted Dark Teal

This is a muted, dark teal under the deterministic OKLCH hue, lightness, and chroma ranges. Its closest standardized CSS named color is Dark Slate Gray (#2F4F4F), measured with straight-line OKLab distance.

Descriptive label
Muted Dark Teal
Recommended text
White · 8.68:1
Relative luminance
0.070961
Build a palette from #21525A in Palette Generator Convert #21525A in Color Converter
Formats UI preview Contrast 50–900 scale Harmonies Matches Related colors Color vision Exports

Copyable values

#21525A in common color formats

Values are calculated from the same opaque sRGB color. Display rounding does not alter the internal calculations.

Color conversions for #21525A
Format Value Action
HEX #21525A
RGB rgb(33 82 90)
HSL hsl(188 46.34% 24.12%)
HSV hsv(188 63.33% 35.29%)
HWB hwb(188 12.94% 64.71%)
XYZ D65 color(xyz-d65 0.054896 0.070958 0.107535)
LAB lab(31.8228% -15.1264 -9.9656)
LCH lch(31.8228% 18.1141 213.3777)
OKLAB oklab(40.8673% -0.046802 -0.026704)
OKLCH oklch(40.8673% 0.053884 209.7077)

Real-world test

Try #21525A on interface components

Preview the source as a primary action, subtle status, form treatment, and card surface. Persistent state controls help touch and keyboard users inspect the same normal, hover, and active colors.

Normal state uses #21525A with white text at 8.68:1.

Action

Primary button

Use the controls above or point to and press the button to inspect its visual states.

Status

Subtle alert badge

A 12% source tint over white provides the background; readable text is selected separately.

Ready for review

Form

Border and focus ring

Source ring on white: 8.68:1 · meets the 3:1 non-text threshold where applicable.

Surface

Card component

The selected state becomes the card surface with its strongest black-or-white text pairing.

Design system Color decision ready Review states and surrounding surfaces before shipping.

Accessibility diagnostics

WCAG contrast for exact color pairs

Each result applies only to the named foreground, background, text size, and requirement. It is not a complete accessibility or component-conformance claim.

Source #21525A Exact pair assessment Results for source text on white appear below.

On white

8.68:1

  • Pass AA normal text · 4.5:1
  • Pass AAA normal text · 7:1
  • Pass AA large text · 3:1
  • Pass UI/non-text where applicable · 3:1
Source #21525A Exact pair assessment Results for source text on black appear below.

On black

2.42:1

  • Fail AA normal text · 4.5:1
  • Fail AAA normal text · 7:1
  • Fail AA large text · 3:1
  • Fail UI/non-text where applicable · 3:1

Use guidance

What this color may be suitable for

Pass in a tested context

Normal-sized text

#21525A reaches 8.31:1 on Hue Codex paper, meeting WCAG AA for normal text in that exact pairing.

Potential fit

Controls and interface graphics

Against Hue Codex paper, the color reaches 8.31:1. That meets the 3:1 color-contrast threshold where WCAG 1.4.11 applies, but states, shape, and non-color cues still need review.

Readable pairing available

Colored surface or button fill

White text provides the stronger black/white pairing on #21525A at 8.68:1. This validates only that text pair, not hover, focus, disabled, or adjacent-color states.

Restrained neutral

Palette role

Its OKLCH chroma of 0.0539 is restrained, which is generally more suitable for surfaces, borders, or neutral system roles than for a vivid accent.

Pair available

Color used as foreground

The stronger black/white background is white at 8.68:1. Always retest against the actual rendered background and text size.

Tested backgrounds

Foreground pairing comparison

#21525A foreground contrast on tested backgrounds
Pair Background Contrast ratio
White#FFFFFF 8.68:1
Hue Codex paper#FBFAF5 8.31:1
Soft neutral#F2EFE6 7.55:1
Black#000000 2.42:1
Hue Codex ink#10212B 1.9:1
Check #21525A on another background in Contrast Checker

Design-system starting point

A perceptual 50–900 reference scale

The source color is preserved at the nearest lightness step. Other swatches keep its OKLCH hue, moderate chroma toward the extremes, and reduce chroma only when needed to remain in sRGB.

50
100
200
300
400
500
600
700 #21525A Source
800
900

This is a Hue Codex reference scale, not a claim that the values match Tailwind, Material, or another framework’s named palette.

Adjust the #21525A scale in Tints, Shades & Tones

Color relationships

Complementary, analogous, and triadic colors

Hue rotations use OKLCH while preserving lightness and requested chroma. When a rotated result falls outside sRGB, chroma is reduced deterministically and disclosed.

Complementary

Source #21525A
Complement

Analogous

Source #21525A
Analogous −30°
Analogous +30°

Triadic

Source #21525A
Triad +120°
Triad +240°

Applied pairing

A small interface check

The source anchors the main action while the complement marks a secondary status. Contrast is selected separately for each fill.

Project color Muted Dark Teal
Complement
Explore #21525A in Color Harmonies

Distance matching

Closest standardized and framework colors

Matches use straight-line OKLab distance ×100. A smaller value means the coordinates are closer in this model; it is not a claim that two tokens are interchangeable in a design system.

CSS named color

Dark Slate Gray

#2F4F4F

OKLab distance ×100: 2.03

Tailwind v4 default

cyan-900

oklch(39.8% 0.07 227.392)

OKLab distance ×100: 2.7 · sRGB preview #104E64

Print boundary

Pantone match not estimated

Reliable print matching needs licensed reference data plus a defined ink, paper, profile, and viewing condition.

Read the print methodology

Color-vision screening

Approximate color-vision-deficiency views

These encoded-sRGB matrix previews are screening approximations. They help reveal possible color-only distinctions but do not reproduce every person’s vision or establish accessibility conformance.

Original#21525A
Approx.

Protanopia

Red-vision deficiency approximation

Original#21525A
Approx.

Deuteranopia

Green-vision deficiency approximation

Original#21525A
Approx.

Tritanopia

Blue-yellow deficiency approximation

Original#21525A
Approx.#444444

Achromatopsia

Monochromatic-vision approximation

Test #21525A with a complete palette in the CVD Simulator

Ready to use

Copy framework-ready color tokens

Exports preserve the source, readable foreground, and generated 50–900 scale. Tailwind v4 CSS-first and Tailwind v3 JavaScript-config formats are labeled separately.

CSS custom properties

Semantic aliases and the complete 50–900 scale.

:root {
  --color-primary: #21525A;
  --color-on-primary: #FFFFFF;
  --color-primary-oklch: oklch(40.8673% 0.053884 209.7077);
  --color-primary-50: #E2FBFF;
  --color-primary-100: #C5E5EB;
  --color-primary-200: #A9CBD1;
  --color-primary-300: #8EB2B9;
  --color-primary-400: #739AA1;
  --color-primary-500: #59828A;
  --color-primary-600: #3F6B73;
  --color-primary-700: #21525A;
  --color-primary-800: #103F46;
  --color-primary-900: #002A30;
}

Tailwind v4 CSS-first theme

Current @theme syntax for bg-brand, text-brand, and scale utilities.

@import "tailwindcss";

@theme {
  --color-brand: #21525A;
  --color-brand-foreground: #FFFFFF;
  --color-brand-50: #E2FBFF;
  --color-brand-100: #C5E5EB;
  --color-brand-200: #A9CBD1;
  --color-brand-300: #8EB2B9;
  --color-brand-400: #739AA1;
  --color-brand-500: #59828A;
  --color-brand-600: #3F6B73;
  --color-brand-700: #21525A;
  --color-brand-800: #103F46;
  --color-brand-900: #002A30;
}

Tailwind v3 / legacy config

CommonJS theme.extend.colors for JavaScript-config projects.

module.exports = {
  theme: {
    extend: {
      colors: {
        brand: {
          '50': '#E2FBFF',
          '100': '#C5E5EB',
          '200': '#A9CBD1',
          '300': '#8EB2B9',
          '400': '#739AA1',
          '500': '#59828A',
          '600': '#3F6B73',
          '700': '#21525A',
          '800': '#103F46',
          '900': '#002A30',
          DEFAULT: '#21525A',
          foreground: '#FFFFFF',
        },
      },
    },
  },
};

Sass variables

Semantic source, foreground, OKLCH, and scale variables.

$color-primary: #21525A;
$color-on-primary: #FFFFFF;
$color-primary-oklch: oklch(40.8673% 0.053884 209.7077);
$color-primary-50: #E2FBFF;
$color-primary-100: #C5E5EB;
$color-primary-200: #A9CBD1;
$color-primary-300: #8EB2B9;
$color-primary-400: #739AA1;
$color-primary-500: #59828A;
$color-primary-600: #3F6B73;
$color-primary-700: #21525A;
$color-primary-800: #103F46;
$color-primary-900: #002A30;

Modern color-mix()

Static fallbacks followed by OKLab tint and shade declarations.

:root {
  --color-primary: #21525A;
  --color-primary-tint: #A9CBD1;
  --color-primary-tint: color-mix(in oklab, var(--color-primary) 72%, white);
  --color-primary-shade: #21525A;
  --color-primary-shade: color-mix(in oklab, var(--color-primary) 82%, black);
}

JSON design data

Source formats, readable text, and the generated scale.

{
    "name": "Muted Dark Teal",
    "hex": "#21525A",
    "rgb": "rgb(33 82 90)",
    "oklch": "oklch(40.8673% 0.053884 209.7077)",
    "recommendedText": "#FFFFFF",
    "scale": {
        "50": "#E2FBFF",
        "100": "#C5E5EB",
        "200": "#A9CBD1",
        "300": "#8EB2B9",
        "400": "#739AA1",
        "500": "#59828A",
        "600": "#3F6B73",
        "700": "#21525A",
        "800": "#103F46",
        "900": "#002A30"
    }
}

Continue the decision

Use #21525A in a complete workflow

Reference values are a starting point. Test the color in its real role, background, states, typography, and surrounding palette before shipping.

Adjust #21525A in Color PickerStart with this exact color and white as the working background for role and accessibility decisions. Build a palette from #21525A in Palette GeneratorUse this exact HEX as the seed for a deterministic, role-based palette. Check #21525A on white in Contrast CheckerStart with this color as the foreground and white as the background, then test the real pair.