Skip to content
cyan · cool

#171e21

a deep, soft cyan · cool · closest name: Black

Token name suggestion: Abyss Reef

RGB
23, 30, 33
HSL
198°, 18%, 11%
CMYK
30, 9, 0, 87
Luminance
0.0122

#171e21 is a deep soft cyan, 198° on the wheel and 73/100 on the cool side. Put white text on it (16.88:1). As text it scores 16.88:1 on white — safe at any size. Nearest name is Black, nearest Tailwind family is gray.

hsl(198 18% 11%)rgb(23 30 33)Base step 950AAA inkCool

At a glance

Every number on this page in one read: what #171e21 is made of, how bright it looks, and which way it leans.

Hex
#171e21
Hue
198°
cyan
Saturation
18%
soft
Lightness
11%
deep
Brightness
13%
HSV value
Perceived
11%
weighted brightness
Luminance
0.0122
WCAG relative
Temperature
Cool
73/100 cool
Color family
Cyan
Tone
Soft
Best ink
White
16.88:1
Closest name
Black
ΔE2000 7.7
Chroma
3.9
LCH, 0–130ish
OKLCH L
0.229
perceptual lightness
Tailwind
gray
500 · ΔE 29.1
Web-safe
#003333
nearest of 216
Where it sits
Hue198° of 360°
Saturation18%
Lightness11%
Saturation × lightness field

Left edge is grey, right edge is full chroma; top is white, bottom is black. The dot is #171e21.

Temperature
Warm ← → Cool73% cool

Reads cool. Warm and cool siblings keep the same lightness, so you can swap one in without redoing your contrast maths.

Luminance by channel
Red15%
Green76%
Blue9%

Green carries most of what the eye calls brightness — that is why WCAG weights it 0.7152.

Every format

HEX#171e21
HEX (8-digit)#171e21ff
RGBrgb(23, 30, 33)
RGBArgba(23, 30, 33, 1)
HSLhsl(198, 18%, 11%)
HSV / HSBhsv(198, 30%, 13%)
HWBhwb(198 9% 87%)
CMYKcmyk(30%, 9%, 0%, 87%)
LABlab(10.7 -2.3 -3.1)
LCHlch(10.7 3.9 233.6)
OKLCHoklch(0.229 0.012 225.7)
XYZ (D65)xyz(1.09, 1.22, 1.62)
Decimal1515041
Display P3color(display-p3 0.090 0.118 0.129)
Web-safe#003333

Copy-ready code

every platformclick to select
/* CSS */
color: #171e21;
background-color: #171e21;
/* CSS custom property */
--brand: #171e21;
/* Tailwind (arbitrary) */
class="text-[#171e21] bg-[#171e21]"
/* SCSS */
$brand: #171e21;
/* SwiftUI */
Color(red: 0.090, green: 0.118, blue: 0.129)
/* UIKit */
UIColor(red: 0.090, green: 0.118, blue: 0.129, alpha: 1)
/* Android XML */
<color name="brand">#171E21</color>
/* Android Compose */
Color(0xFF171E21)
/* Flutter */
Color(0xFF171E21)
/* Python / OpenCV (BGR) */
(33, 30, 23)
/* Python / PIL (RGB) */
(23, 30, 33)
/* Java AWT */
new Color(23, 30, 33)
/* .NET */
Color.FromArgb(255, 23, 30, 33)
/* OpenGL / Unity (0–1) */
(0.0902f, 0.1176f, 0.1294f, 1f)
/* LaTeX */
\definecolor{brand}{RGB}{23,30,33}
modern cssclick to select
/* mix without leaving CSS */
background: color-mix(in oklab, #171e21 85%, white);
border-color: color-mix(in oklab, #171e21 40%, transparent);
/* theme-aware in one line */
color: light-dark(#34444B, #DBE3E6);
/* relative colour syntax */
--hover: hsl(from #171e21 h s calc(l - 7));

Design tokens

The same ramp in the four formats a team actually needs. Paste one and the whole palette lands with it.

css custom propertiesclick to select
:root {
  --brand-50: #F6F8F8;
  --brand-100: #EEF1F2;
  --brand-200: #D9E0E3;
  --brand-300: #BDCBD1;
  --brand-400: #9CB1BA;
  --brand-500: #7B97A3;
  --brand-600: #648390;
  --brand-700: #546D78;
  --brand-800: #435760;
  --brand-900: #334147;
  --brand-950: #171e21;
  --brand: #171e21;
  --brand-ink: #ffffff;
  --brand-surface: #F6F8F9;
  --brand-border: #CFD9DE;
  --brand-hover: #080B0C;
  --brand-pressed: #000000;
}
@media (prefers-color-scheme: dark) {
  :root {
    --brand-surface: #171E21;
    --brand-ink: #DBE3E6;
  }
}
tailwind.config.jsclick to select
theme: {
  extend: {
    colors: {
      brand: {
        50: '#F6F8F8',
        100: '#EEF1F2',
        200: '#D9E0E3',
        300: '#BDCBD1',
        400: '#9CB1BA',
        500: '#7B97A3',
        600: '#648390',
        700: '#546D78',
        800: '#435760',
        900: '#334147',
        950: '#171e21',
        DEFAULT: '#171e21',
      },
    },
  },
}
scss mapclick to select
$brand: (
  '50': #F6F8F8,
  '100': #EEF1F2,
  '200': #D9E0E3,
  '300': #BDCBD1,
  '400': #9CB1BA,
  '500': #7B97A3,
  '600': #648390,
  '700': #546D78,
  '800': #435760,
  '900': #334147,
  '950': #171e21,
);
$brand-base: #171e21;
$brand-ink: #ffffff;

@function brand($step) { @return map-get($brand, $step); }
w3c design tokens (json)click to select
{
  "color": {
    "brand": {
      "50": { "$value": "#F6F8F8", "$type": "color" },
      "100": { "$value": "#EEF1F2", "$type": "color" },
      "200": { "$value": "#D9E0E3", "$type": "color" },
      "300": { "$value": "#BDCBD1", "$type": "color" },
      "400": { "$value": "#9CB1BA", "$type": "color" },
      "500": { "$value": "#7B97A3", "$type": "color" },
      "600": { "$value": "#648390", "$type": "color" },
      "700": { "$value": "#546D78", "$type": "color" },
      "800": { "$value": "#435760", "$type": "color" },
      "900": { "$value": "#334147", "$type": "color" },
      "950": { "$value": "#171e21", "$type": "color" }
    },
    "brandInk": { "$value": "#ffffff", "$type": "color" }
  }
}

Best text color

Only one of black and white can be right. This is the one, with the number that proves it.

Readable at a glance#ffffff on #171e21 · 16.88:1
Use #ffffffAAA at every size.
Aa
12px
Aa
16px
Aa
24px
Aa
White text · 16.88:1 · recommended
AA pass · AA large pass · AAA pass
Aa
Black text · 1.24:1
AA fail · AA large fail · AAA fail
Reading the other direction: #171e21 as text scores 16.88:1 on white and 1.24:1 on black.
Best tinted ink on it, if plain black or white feels flat: #F0F3F5 at 15.15:1.

Make it accessible

A contrast checker tells you that you failed. This tells you what to ship instead — same hue, same saturation, lightness moved only as far as WCAG demands.

The quick fox
#171e21 · 16.88:1
AA on whitealready passes
#171e21
The quick fox
#171e21 · 16.88:1
AAA on whitealready passes
#171e21
The quick fox
#5E7B87 · 4.66:1
AA on black+34% L
#5E7B87
The quick fox
#819CA7 · 7.25:1
AAA on black+47% L
#819CA7

Large text — 24px regular or 18.66px bold and above — only needs 3:1, so #171E21 is enough for headings on white. Non-text elements such as icons, chart strokes and focus rings also sit at 3:1 under WCAG 2.2 (1.4.11).

Accessibility — WCAG contrast

Aa
#171e21 on white: 16.88:1
AA ✓ pass · AA-large · AAA
Aa
#171e21 on black: 1.24:1
AA ✗ fail · AA-large · AAA
Against the neutral ladder

Contrast is symmetric, so each row covers both directions: #171e21 as text on that neutral, and that neutral as text on #171e21.

NeutralRatioBoth directions
White16.88:1AaAa
Slate 5016.13:1AaAa
Slate 10015.41:1AaAa
Slate 20013.69:1AaAa
Slate 30011.37:1AaAa
Slate 4006.58:1AaAa
Slate 5003.55:1AaAa
Slate 6002.23:1AaAa
Slate 7001.63:1AaAa
Slate 8001.15:1AaAa
Slate 9001.06:1AaAa
Black1.24:1AaAa
Colour vision deficiency
true color
protanopia · #1C1E21
deuteranopia · #1B1C21
tritanopia · #141F1F

Roughly one man in twelve has some form of colour vision deficiency. If any of the three panels above is hard to tell apart from a neighbouring colour in your palette, add a shape, an icon or a label so the meaning does not rest on hue alone.

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #171e21 is pinned to step 950; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F6F8F8
#EEF1F2
#D9E0E3
#BDCBD1
#9CB1BA
#7B97A3
#648390
#546D78
#435760
#334147
#171e21
Base = 950Lightest = 50 · #F6F8F8Darkest = 950 · #171e21Text step on white = 700
Perceptual ramp — OKLCH

The same eleven steps expressed in OKLCH, where equal lightness numbers actually look equally spaced. HSL ramps go muddy in the yellows and washed out in the blues; this one does not. Modern browsers render it natively — the hex ramp above is the fallback.

50100200300400500600700800900950
oklch tokensclick to select
:root {
  --brand-50: oklch(0.97 0.003 225.7);
  --brand-100: oklch(0.94 0.005 225.7);
  --brand-200: oklch(0.88 0.007 225.7);
  --brand-300: oklch(0.80 0.009 225.7);
  --brand-400: oklch(0.72 0.011 225.7);
  --brand-500: oklch(0.64 0.012 225.7);
  --brand-600: oklch(0.56 0.012 225.7);
  --brand-700: oklch(0.48 0.011 225.7);
  --brand-800: oklch(0.40 0.010 225.7);
  --brand-900: oklch(0.32 0.008 225.7);
  --brand-950: oklch(0.24 0.006 225.7);
}

Colors that work with #171e21

Not a palette — a role sheet. Each swatch answers one question you will hit while building the component.

Text on it#ffffff
White wins here
Surface#F6F8F9
Tinted page background
Border#CFD9DE
Hairlines and dividers
Muted text#5E7B87
Captions on the surface
Accent#221716
Second voice, not a rival
Dark variant#34444B
Hover, pressed, headers
Light variant#F0F3F5
Selected rows, tints
Dark surface#171E21
Dark-mode background
Hover#080B0C
One step down in lightness
Pressed#000000
Two steps down
Disabled#455A63
Chroma pulled out
Focus ring#1C2B31
Offset from the fill so it reads
Light mode
Everything in its place

Surface, border, heading and body all derive from this one hue, so the screen stays coherent without a second palette.

Primary actionSecondaryBadge
Dark mode
Same hue, inverted

Lightness flips, hue holds. The accent stays the anchor in both themes.

Primary actionSecondaryAccent

In real components

The same eight roles, wired into the interface patterns you will actually build with them. Every state below is a computed value, not a mock-up.

Buttons and states
Save changesHoverPressedDisabled
OutlineSubtleLinkFocused
Form field
you@company.com

Focus ring uses the light variant so the field still reads as one shape.

Send me product updates
Notice
Your export is ready

The file stays available for seven days. Download it before it expires.

NewBetaDraft
Data
Storage used68%
Acme LtdActive
NorthwindTrial
GlobexActive

How to use #171e21

Derived from its contrast, chroma and lightness — not from taste.

Works well for
  • Body text and links on white
  • Charts, tags and secondary surfaces
  • Headers, footers and dark-mode surfaces
  • Brand accents, badges and data highlights
Use with care
  • Text on black or near-black surfaces
  • Black text placed on it
  • Thin strokes and 1px borders — they disappear on light UI
  • Pairing with a same-lightness hue — edges vibrate
Minimum size as text on white
Any size
Safe as a fill behind white type
Yes
Safe as a 1px border on white
Yes

Meaning and mood

What a colour in this family tends to signal, and how this particular chroma and lightness change the reading.

cleantechnicalfreshclinical

Cyan reads as water, air and infrastructure: cool, hygienic, engineered.

The muted chroma softens the association — it reads considered rather than loud, which suits long-form and data-heavy screens. The low lightness adds weight and formality.

Worth knowing

At high lightness it disappears into white surfaces and thin strokes vanish entirely.

Reads as
  • FormalityHigh
  • EnergyMedium
  • Weight89/100
  • TemperatureCool
  • ApproachabilityReserved

Colour associations are cultural and vary by market. Treat these as a starting point for a conversation with your audience, not a finding about them.

Similar colors

One move away from this hex in each direction. Every swatch is its own page.

Color relationships

The wheel positions with their names attached, so you can grab the one you actually need.

Complementary#211A17
Analogous left#17211F
Analogous right#171921
Split-complement 1#211719
Split-complement 2#211F17
Triadic 1#21171E
Triadic 2#1E2117
Tetradic#1F1721
On the wheel
Base+30°−30°+120°+240°+180°198°

#171e21 sits at 198°. Every dot is a harmony position and links to its own page in the table alongside.

RGB percentages

Red9.0%
Green11.8%
Blue12.9%
R · 0–255
23
0x17
G · 0–255
30
0x1e
B · 0–255
33
0x21

CMYK percentages

Cyan30.3%
Magenta9.1%
Yellow0.0%
Key (black)87.1%

Total ink coverage is 127%. Most commercial presses cap around 300% — above that, sheets stop drying properly.

Color previews

#171e21 text on a black background

contrast 1.24:1

Card sample

#171e21 text on a white background

contrast 16.88:1

Card sample

#171e21 on grey

15.41:1

#171e21 on its own surface

15.85:1

#171e21 on its dark surface

1.00:1

CSS3 live lab

Text font color

The quick brown fox

color: #171e21;
Background color
Panel with #171e21 background
background-color: #171e21;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #171e21;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(23, 30, 33, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(23, 30, 33, 0.45);
Border & gradient
Gradient panel
border: 3px solid #171e21;
background: linear-gradient(135deg, #171e21, #171721);
Gradient text

Gradient headline

background: linear-gradient(90deg, #171e21, #191721);
-webkit-background-clip: text;
color: transparent;
Focus ring
Focused control
outline: 2px solid #171e21;
outline-offset: 3px;
Underline & caret

Marked up text

text-decoration-color: #171e21;
caret-color: #171e21;
Left rule
Pull quote or callout
border-left: 4px solid #171e21;
Ring + tint
Selected chip
background: #F0F3F5;
box-shadow: inset 0 0 0 2px #171e21;
Conic badge
68%
background: conic-gradient(#171e21 68%, #e2e8f0 0);

Transparency

What each alpha value actually composites to. The top row is #171e21 over white; the bottom row is the same alpha over a checkerboard, so you can see what survives on a photo or a video.

Bottom row of hexes is the flattened result over white — use those when a design tool refuses transparency, or when you need a solid fallback.

alpha in every syntaxclick to select
rgba(23, 30, 33, 0.5)
rgb(23 30 33 / 50%)
#171e2180
hsl(198 18% 11% / 50%)
color-mix(in srgb, #171e21 50%, transparent)
Alpha8-digit hexFlat on white
10%#171e211a#E8E9E9
20%#171e2133#D1D2D3
40%#171e2166#A2A5A6
60%#171e2199#74787A
80%#171e21cc#454B4D

Gradients from #171e21

Six recipes, each built from this hex and shown with the exact CSS that produced it.

Elevation
Same hue, three lightnesses — safe anywhere
background: linear-gradient(135deg, #303F45, #171e21 45%, #34444B);
Duotone
A short hue run reads richer than a flat fill
background: linear-gradient(120deg, #171e21, #0B0A0F);
Complement sweep
Loud — keep it behind large type only
background: linear-gradient(90deg, #171e21, #211A17);
Spotlight
Hero panels and app headers
background: radial-gradient(120% 120% at 20% 0%, #3D4F57 0%, #171e21 45%, #34444B 100%);
Soft wash
Section backgrounds that stay readable
background: linear-gradient(180deg, #F6F8F9, #ffffff);
Mesh
Ambient background, no image weight
background: radial-gradient(60% 60% at 15% 20%, #2C3F3A 0%, transparent 60%), radial-gradient(55% 55% at 85% 15%, #242533 0%, transparent 60%), radial-gradient(70% 70% at 50% 95%, #34444B 0%, transparent 65%), #171e21;

Monochromatic scale

Palettes built from #171e21

Shades — darker

Tints — lighter

Tones — desaturated

Color harmonies

Nearest named colors

Ranked with CIEDE2000 across all 139 CSS keywords. Under ΔE 2 the eye stops telling them apart; over ΔE 10 they are plainly different colors.

#171e21 in the real world

Where a color in this family tends to land, and the interface roles it is usually asked to play.

Industries
TechnologyTravelHealthcareMedia
Common UI roles
ButtonsLinksFocus statesCharts
Print note

Converts to four-color process without much drama. Proof it anyway.

On screens

Very dark values collapse into each other on cheap panels — leave more lightness between your darkest steps than the numbers suggest.

In dark mode

Too dim on dark surfaces at 1.24:1 — lift it to #5E7B87 for body text, or reserve it for fills.

Explore nearby colors

Small, deliberate steps away from this hex — useful when you are hunting for the version of a colour that finally feels right.

#171e21, answered

What color is #171e21?

#171e21 is a deep soft cyan, closest to Black (ΔE2000 7.7). It sits at 198° on the hue wheel with 18% saturation and 11% lightness, which reads as cool.

What is the RGB value of #171e21?

rgb(23, 30, 33) — 23 red, 30 green and 33 blue out of 255, or 9% / 11.8% / 12.9% by channel.

What is #171e21 in HSL and HSV?

hsl(198, 18%, 11%) and hsv(198, 30%, 13%). HSL is what CSS takes; HSV is what your design tool's picker shows, which is why the saturation numbers rarely match.

Is #171e21 a light or a dark color?

It is a dark color. Relative luminance is 0.0122 and perceived brightness is 11%, so white text on it reaches 16.88:1.

Should I use black or white text on #171e21?

White. It scores 16.88:1 against #171e21, versus 1.24:1 for black — AAA at any size.

Is #171e21 accessible on a white background?

#171e21 on white scores 16.88:1, which clears AAA at every size.

What is the complementary color of #171e21?

#211A17 sits directly opposite on the wheel. Softer options are the split-complements #211719 and #211F17, which give the same contrast with far less vibration.

What colors go well with #171e21?

For interface work: #F6F8F9 as the surface, #CFD9DE for borders, #5E7B87 for secondary text, #221716 as an accent and #34444B for hover and pressed states. For a palette, the analogous pair #17211F and #171921 stays calm, while #211A17 is the loudest partner.

What is #171e21 in CMYK for printing?

cmyk(30%, 9%, 0%, 87%). This is a screen-to-ink approximation — ask your printer for a proof before committing to a run.

Is #171e21 warm or cool?

Cool — it scores 73 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #172120; nudged cooler, #161C22.

Which Tailwind color is closest to #171e21?

The gray family — its 500 step is #6b7280, ΔE2000 29.1 away. That is a visible difference, so define #171e21 as a custom token rather than reaching for the built-in.

How do I use #171e21 in Tailwind CSS?

Inline it as an arbitrary value with bg-[#171e21] or text-[#171e21], or register the whole ramp under theme.extend.colors.brand so you get bg-brand-500 and friends. The generated 50–950 scale on this page is ready to paste into your config.

What is #171e21 with 50% opacity?

rgba(23, 30, 33, 0.5), or #171e2180 in eight-digit hex. Over white that composites to #8B8F90; over black, #0C0F11.

Is #171e21 a web-safe color?

No. The nearest web-safe colour is #003333, ΔE2000 13.3 away. The palette only matters for legacy displays and some email clients now.

What does the color #171e21 mean?

As a cyan, it reads clean, technical, fresh. Cyan reads as water, air and infrastructure: cool, hygienic, engineered. At this moderate chroma the association is present but not shouted.

What gradient works with #171e21?

The safest is same-hue elevation: linear-gradient(135deg, #303F45, #171e21 45%, #34444B). For more colour, a short hue run to #0B0A0F keeps it rich without turning muddy.

Work with #171e21 in the Color Lab

Every tool opens with this colour already loaded.

Every value on this page is computed from #171e21 at request time — conversions, contrast ratios and ΔE distances are calculated, never looked up.