CSS named color

Dark Slate Gray #2F4F4F

The CSS keyword darkslategray is #2F4F4F. It is a dark grayish teal in the cyan family. In OKLCH it sits at lightness 0.403, chroma 0.038 and hue 195.8°.

Relative luminance: 0.0676
OKLCH L · C · h: 0.403 · 0.038 · 195.8
Best text: White 8.92:1
Hue family: Cyan

Inspect this color Check contrast

#2F4F4F color codes

HEX: #2F4F4F
RGB: rgb(47, 79, 79)
HSL: hsl(180, 25%, 25%)
OKLCH: oklch(0.403 0.038 195.8)
OKLab: oklab(0.403 -0.036 -0.010)
CIELAB (D65): L* 31.26, a* -11.72, b* -3.72
XYZ (D65): X 5.38, Y 6.76, Z 8.42
CMYK (naive): cmyk(41%, 0%, 0%, 69%)

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 #2F4F4F accessible?

White text on it reaches 8.92:1, passing AAA. Black text fails at 2.35:1.

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

2.35:1
- AA fails
- AA large fails
- AAA fails
- APCA Lc +13
White text on it

8.92:1
- AA passes
- AA large passes
- AAA passes
- APCA Lc −94
As text on black

2.35:1
- AA fails
- AA large fails
- AAA fails
- APCA Lc −11
As text on white

8.92:1
- AA passes
- AA large passes
- AAA passes
- APCA Lc +90

Nearest versions that pass 4.5:1

For text on white

#2F4F4F 8.92:1

It already reaches 8.92:1 on white, so no change is needed.
For text on black

#5A7B7B 4.55:1

Lightening its OKLCH lightness from 0.40 to 0.56 reaches 4.55:1 on black, keeping the hue.

Compare both in the Contrast System

Checking another pair? Use the Contrast Checker.

Studio

Adjust #2F4F4F 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 #2F4F4F

Eleven OKLCH lightness steps at this hue, each with its contrast against white and black. #2F4F4F sits at step 800.

50#DFFCFC

White
1.07
Black
19.46
100#D4F2F2

White
1.18
Black
17.78
200#BFDFDE

White
1.41
Black
14.82
300#A4C5C5

White
1.84
Black
11.37
400#87A9A9

White
2.53
Black
8.27
500#6C8E8D

White
3.56
Black
5.89
600#557676

White
4.95
Black
4.23
700#3F5F5F

White
6.96
Black
3.01
800This color#2F4F4F

White
8.92
Black
2.35
900#142E2E

White
14.38
Black
1.45
950#041A1A

White
17.98
Black
1.16

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

Gamut

How vivid #2F4F4F can get

At its lightness and hue, sRGB reaches OKLCH chroma 0.069; #2F4F4F uses 55% of it. Display P3, which many recent phones and laptops show, reaches 0.092 there: 34% more.

sRGB
Display P3
Rec. 2020
Dominant wavelength

OKLCH chroma: 0.038
sRGB edge: 0.069
Display P3 edge: 0.092
Rec. 2020 edge: 0.150
Dominant wavelength: 491 nm
Excitation purity: 19%
Chromaticity: x 0.2617, y 0.3289

This color#2F4F4F
Most vivid in sRGB#005454
Most vivid in Display P3oklch(0.403 0.092 195.8)

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

Use the wider color where screens show it

.accent {
  color: #2f4f4f;
}
@media (color-gamut: p3) {
  .accent { color: color(display-p3 0 0.334 0.343); }
}

Mixing

Mixing #2F4F4F

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%#97A7A7
OKLab50%#92A3A3
OKLCH50%#92A3A3

Black #000000

sRGB50%#182828
OKLab50%#0C1919
OKLCH50%#0C1919

Its complement #5B4042

sRGB50%#454849
OKLab50%#484849
OKLCH50%#46465C

In CSS

/* A gradient and a mix, worked out in OKLCH */
background: linear-gradient(in oklch, #2f4f4f, white);
color: color-mix(in oklch, #2f4f4f 50%, white);

In use

#2F4F4F 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, 4.5:18.92:1 Passes
Link and body-size textText, 4.5:18.92:1 Passes
Large headingLarge text, 3:18.92:1 Passes
Icons, borders and focus ringsNon-text, 3:18.92:1 Passes

Dark page

Button labelText, 4.5:18.92:1 Passes
Link and body-size textText, 4.5:12.09:1 Fails
Large headingLarge text, 3:12.09:1 Fails
Icons, borders and focus ringsNon-text, 3:12.09:1 Fails

For text on this page, the nearest shade that passes is #618382 4.52:1

Color vision

How #2F4F4F looks with color blindness

Deuteranopia changes it most, ΔE2000 13.2; tritanopia changes it least, 3.6.

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

#4B4C4F ΔE2000 13.0

Distinct

Reads as dark gray
Deuteranopia

No working green (medium-wavelength) cones

#45484F ΔE2000 13.2

Distinct

Reads as dark gray
Tritanopia

No working blue (short-wavelength) cones

#22514F ΔE2000 3.6

Close match

Reads as dark muted teal
Achromatopsia

No cone color vision; lightness only

#4A4A4A ΔE2000 12.8

Distinct

Reads as dark gray

Pairing check

Checked against its complement, #5B4042. Their lightness contrast is only 1.04:1, so where hue collapses, add a label, icon or pattern.

Vision	The pair	ΔE2000	Verdict
Normal vision	#2F4F4F · #5B4042	31.7	Stays distinct
Protanopia	#4B4C4F · #454442	4.2	Easily confused
Deuteranopia	#45484F · #4B4942	8.7	Harder to tell apart
Tritanopia	#22514F · #603E41	36.1	Stays distinct
Achromatopsia	#4A4A4A · #474747	1.0	Easily confused

Harmony

Color harmonies for #2F4F4F

Its complement is #5B4042, a dark grayish wine, 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#2F4F4F
Complement#5B4042

Complementary

Open in Harmony Studio

−30°#354F44
Base#2F4F4F
+30°#324D58

Analogous

Open in Harmony Studio

Base#2F4F4F
+120°#514257
+240°#544631

Triadic

Open in Harmony Studio

Base#2F4F4F
+150°#58404D
+210°#5A4237

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-darkslategray: #2f4f4f;
}

Tailwind config

// tailwind.config.js
module.exports = {
  theme: {
    extend: {
      colors: {
        darkslategray: '#2f4f4f',
      },
    },
  },
};

Tailwind v4 theme

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

@theme {
  --color-darkslategray: oklch(0.403 0.038 195.8);
}

Design token (W3C DTCG)

{
  "color": {
    "darkslategray": {
      "$type": "color",
      "$value": {
        "colorSpace": "srgb",
        "components": [0.1843, 0.3098, 0.3098],
        "hex": "#2f4f4f"
      },
      "$description": "CSS named color darkslategray"
    }
  }
}

SwiftUI color

import SwiftUI

enum Palette {
    static let darkslategray = Color(.sRGB, red: 0.184, green: 0.310, blue: 0.310, opacity: 1)
}

Jetpack Compose color

import androidx.compose.ui.graphics.Color

object Palette {
    val Darkslategray = Color(0xFF2F4F4F)
}

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 #2F4F4F in the tools

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

Dark Slate Gray #2F4F4F

#2F4F4F color codes

Contrast: is #2F4F4F accessible?

Black text on it

White text on it

As text on black

As text on white

Nearest versions that pass 4.5:1

Adjust #2F4F4F live

Shades and tints of #2F4F4F

How vivid #2F4F4F can get

Mixing #2F4F4F

#2F4F4F in an interface

How #2F4F4F looks with color blindness

Protanopia

Deuteranopia

Tritanopia

Achromatopsia

Pairing check

Color harmonies for #2F4F4F

Complementary

Analogous

Triadic

Split-complementary

Design tokens

CSS custom property

Tailwind config

Tailwind v4 theme

Design token (W3C DTCG)

SwiftUI color

Jetpack Compose color

The nearest match in each system

Similar colors

Open #2F4F4F in the tools