#172B21

sRGB: 23 / 43 / 33

Fading shadows awaken with sunrise
Withered branches shimmer across boundless heavens
Distant echoes surrender to silence

#172B21 belongs to the green-cyan family. Its hex code tells a screen to mix 23 red, 43 green and 33 blue on a scale of 0 to 255. On the HSL wheel, hue is a position around a circle: 150.0° lands in the green-cyan region. Its 30.3% saturation makes it partway between gray and the most vivid version of this hue at this lightness. HSL lightness is 12.9% on a scale from black (0%) to white (100%). Of black and white lettering, white has the clearer light-to-dark separation on this background (14.96:1), which helps the shapes of letters stand out.

Color conversions

sRGB (8-bit): 23, 43, 33
HSL: 150.00°, 30.30%, 12.94%
HSV / HSB: 150.00°, 46.51%, 16.86%
CMYK (approx.): 46.51%, 0.00%, 23.26%, 83.14%
CIE XYZ (D65, Y = 100 for white): 1.492, 2.020, 1.750
CIELAB (D65, 2° observer): 15.590, -10.980, 3.995
WCAG relative luminance: 0.02020
24-bit decimal: 1518369

CMYK uses a profile-free approximation. Printed output depends on the press, ink and paper. Lab uses a D65 white point.

Text contrast

Contrast tells you how clearly lettering separates from #172B21 in light and dark. The ratio compares relative luminance, a measure of light weighted for human vision. Identical colors give 1:1 and black against white gives 21:1. A ratio of 2.99:1 falls just below the 3:1 AA minimum for large text. Body text needs at least 4.5:1 because its finer strokes are harder to distinguish.

Black text: 1.40:1

Normal text: Fail
Large text: Fail

White text: 14.96:1

Normal text: AAA
Large text: AAA

AA and AAA are WCAG accessibility levels. AAA sets a higher bar: 7:1 for normal text and 4.5:1 for large text. Large text begins at 18 pt regular or 14 pt bold. Ratings use the unrounded ratio.

Reference: WCAG text contrast guidance

Palettes & scales

Harmonies rotate the hue. Scales mix the starting color with white, black or middle gray in 20% steps in encoded sRGB.

Complementary

#2B1721 sits half a turn (180°) from #172B21 on the HSL wheel. Keeping saturation and lightness steady while crossing to the opposite hue gives you a contrasting accent. Check text contrast separately before using the pair for lettering.

#172B21 #2B1721

Analogous

#172B17 and #172B2B sit 30° to either side of #172B21. The three hues are neighbors on the wheel, so you can change the color of a border or highlight while keeping it close to the original.

#172B17 #172B21 #172B2B

Triadic

#172B21, #21172B and #2B2117 are spaced 120° apart, forming a triangle on the wheel. Try one for the main color and the other two for accents.

#172B21 #21172B #2B2117

Split complementary

Start at #172B21 and look across the wheel. #2B172B and #2B1717 sit 30° to either side of its exact opposite, giving you two different accent choices.

#172B21 #2B172B #2B1717

Square

Starting with #172B21, each quarter turn (90°) takes you to the next hue: #17172B, #2B1721, then #2B2B17. Across the square, #172B21 pairs with #2B1721, and #17172B with #2B2B17.

#172B21 #17172B #2B1721 #2B2B17

Tetradic

#172B21 and #2B1721 are opposites, as are #17212B and #2B2117. Together they form a rectangle on the wheel, with alternating gaps of 60° and 120°.

#172B21 #17212B #2B1721 #2B2117

Tints

Mixing #172B21 with white in 20% steps produces this scale. The first mixture, #45554D, keeps 80% of the original. By #D1D5D3, the mixture is 80% white.

#172B21 #45554D #74807A #A2AAA6 #D1D5D3 #FFFFFF

Shades

Mixing #172B21 with black in 20% steps produces this scale. The first mixture, #12221A, keeps 80% of the original. By #050907, the mixture is 80% black.

#172B21 #12221A #0E1A14 #09110D #050907 #000000

Tones

Mixing #172B21 with middle gray in 20% steps produces this scale. The first mixture, #2C3C34, keeps 80% of the original. By #6B6F6D, the mixture is 80% middle gray.

#172B21 #2C3C34 #414D47 #565E5A #6B6F6D #808080

Copy color codes

Hex, RGB and HSL are three ways to write this screen color. Paste any of them into a CSS color property.

Hex

#172B21

RGB

rgb(23 43 33)

HSL

hsl(150.000 30.303% 12.941%)

CSS example

.color-sample {
  background-color: #172B21;
  color: #FFFFFF;
}

Channel breakdown

RGB

#172B21 uses 23 red, 43 green and 33 blue. Each bar shows how much of that channel’s 0–255 range the screen uses.

Red 9.0%

Green 16.9%

Blue 12.9%

CMYK

A simple CMYK estimate for #172B21 is 46.5% cyan, 0.0% magenta, 23.3% yellow and 83.1% black. These are ink amounts; a printer profile is needed to predict the result on paper.

Cyan 46.5%

Magenta 0.0%

Yellow 23.3%

Black 83.1%

Nearby colors

The nearest shorthand match is #113322. Its matching digit pairs let you write it as #132 in CSS. For a modern design, keep #172B21 when you want an exact match. Use its web-safe neighbor, #003333, when matching a legacy palette of 216 colors.

Nearest shorthand: #113322 Nearest web-safe: #003333

Gradient to complement

#172B21 #1A2821 #1E2421 #212121 #241E21 #281A21 #2B1721

Color vision previews

Compare how #172B21 appears in each simulation. When two chart lines or status indicators become hard to tell apart, a label, shape or line pattern gives readers another way to distinguish them. Individual perception varies.

Protanopia

A red–green color vision deficiency. Without a distinct response from long-wavelength cones, some reds and greens can look alike, and reds can appear darker.

#2A2820

Deuteranopia

A red–green color vision deficiency. Without a distinct response from medium-wavelength cones, some greens can be difficult to distinguish from reds or browns.

#272622

Tritanopia

A blue–yellow color vision deficiency. Without a distinct response from short-wavelength cones, blue can resemble green, and yellow can resemble pink.

#122B28

Protanomaly (50%)

An altered long-wavelength cone response can make reds appear dimmer and harder to distinguish from greens. This swatch shows the model’s halfway setting.

#252921

Deuteranomaly (50%)

An altered medium-wavelength cone response can reduce the visible difference between reds and greens. This swatch shows the model’s halfway setting.

#232821

Tritanomaly (50%)

An altered short-wavelength cone response can make blue harder to distinguish from green. This swatch shows the model’s halfway setting.

#172B24

Grayscale (luminance)

This design check removes hue and preserves relative luminance so you can compare light and dark areas.

#272727

Partial grayscale (50% blend)

This design check mixes the original color halfway toward its grayscale equivalent in linear light. Use it to see how a design holds up as color fades.

#202924

Reference: National Eye Institute: Types of Color Vision Deficiency

Technical reference

CAM16 and CIECAM02 below assume D65 white, an average surround, background Y of 20 against white at 100, and adapting luminance of 4.07 cd/m².

Linear sRGB

These channels scale with emitted light. Use them for lighting calculations and physically meaningful blends.

R 0.00857 G 0.02416 B 0.01521

Display P3

P3 displays can reproduce a wider range of reds and greens. These coordinates reproduce this same sRGB swatch on a color-managed P3 display.

R 0.10816 G 0.16662 B 0.13208

Linear Display P3

These P3 channels are proportional to light, before display encoding.

R 0.01134 G 0.02364 B 0.01574

CIE xyY

The x and y coordinates locate chromaticity on a diagram. Y gives relative luminance on a scale where white is 100.

x 0.284 y 0.384 Y 2.020

CMY

Ideal cyan, magenta and yellow are the complements of the encoded red, green and blue channels.

C % 90.980 M % 83.137 Y % 87.059

Binary RGB

Each eight-bit group represents one channel. Together they store the 24-bit hex color.

00010111 00101011 00100001