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#2f3939

a deep, muted cyan · cool · closest name: Dark Slate Gray

RGB
47, 57, 57
HSL
180°, 10%, 20%
CMYK
18, 0, 0, 78
Luminance
0.0383

At a glance

Every number on this page in one read: what #2f3939 is made of, how bright it looks, and which way it leans.

Hex
#2f3939
Hue
180°
cyan
Saturation
10%
muted
Lightness
20%
deep
Brightness
22%
HSV value
Perceived
21%
weighted brightness
Luminance
0.0383
WCAG relative
Temperature
Cool
60/100 cool
Color family
Cyan
Tone
Muted
Best ink
White
11.90:1
Closest name
Dark Slate Gray
ΔE2000 9.6
Where it sits
Hue180° of 360°
Saturation10%
Lightness20%
Temperature
Warm ← → Cool60% cool

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

Every format

HEX#2f3939
RGBrgb(47, 57, 57)
HSLhsl(180, 10%, 20%)
CMYKcmyk(18%, 0%, 0%, 78%)
LABlab(23.1 -4.2 -1.4)
LCHlch(23.1 4.4 198.6)
OKLCHoklch(0.335 0.013 196.5)
Decimal3094841
Display P3color(display-p3 0.184 0.224 0.224)

Copy-ready code

/* CSS */
color: #2f3939;
background-color: #2f3939;
/* Tailwind (arbitrary) */
class="text-[#2f3939] bg-[#2f3939]"
/* SCSS */
$brand: #2f3939;
/* SwiftUI */
Color(red: 0.184, green: 0.224, blue: 0.224)
/* Android */
Color.parseColor("#2f3939")
/* Flutter */
Color(0xFF2F3939)
/* Python / OpenCV (BGR) */
(57, 57, 47)

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 #2f3939 · 11.90:1
Use #ffffffAAA at every size.
Aa
White text · 11.90:1 · recommended
AA pass · AA large pass · AAA pass
Aa
Black text · 1.77:1
AA fail · AA large fail · AAA fail
Reading the other direction: #2f3939 as text scores 11.90:1 on white and 1.77:1 on black.

Accessibility — WCAG contrast

Aa
#2f3939 on white: 11.90:1
AA ✓ pass · AA-large · AAA
Aa
#2f3939 on black: 1.77:1
AA ✗ fail · AA-large · AAA
true color
protanopia · #383839
deuteranopia · #363639
tritanopia · #2C3A39

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #2f3939 is pinned to step 900; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F7F8F8
#EFF1F1
#DBE1E1
#C2CCCC
#A3B3B3
#849A9A
#6F8686
#5C7070
#4A5959
#2f3939
#232A2A
Base = 900Lightest = 50 · #F7F8F8Darkest = 950 · #232A2A
:root {
  --brand-50: #F7F8F8;
  --brand-100: #EFF1F1;
  --brand-200: #DBE1E1;
  --brand-300: #C2CCCC;
  --brand-400: #A3B3B3;
  --brand-500: #849A9A;
  --brand-600: #6F8686;
  --brand-700: #5C7070;
  --brand-800: #4A5959;
  --brand-900: #2f3939;
  --brand-950: #232A2A;
  --brand: #2f3939;
  --brand-ink: #ffffff;
}

Colors that work with #2f3939

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#F7F8F8
Tinted page background
Border#D2DADA
Hairlines and dividers
Muted text#687E7E
Captions on the surface
Accent#3B2D30
Second voice, not a rival
Dark variant#3A4646
Hover, pressed, headers
Light variant#F1F3F3
Selected rows, tints
Dark surface#191F1F
Dark-mode background
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

How to use #2f3939

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

Works well for
  • Body text and links on white
  • Borders, dividers and quiet backgrounds
  • Long-form reading 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

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#392F2F
Analogous left#2F3934
Analogous right#2F3439
Split-complement 1#392F34
Split-complement 2#39342F
Triadic 1#392F39
Triadic 2#39392F
Tetradic#342F39

RGB percentages

Red18.4%
Green22.4%
Blue22.4%

CMYK percentages

Cyan17.5%
Magenta0.0%
Yellow0.0%
Key (black)77.6%

Color previews

#2f3939 text on a black background

contrast 1.77:1

Card sample

#2f3939 text on a white background

contrast 11.90:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #2f3939;
Background color
Panel with #2f3939 background
background-color: #2f3939;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #2f3939;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(47, 57, 57, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(47, 57, 57, 0.45);
Border & gradient
Gradient panel
border: 3px solid #2f3939;
background: linear-gradient(135deg, #2f3939, #2F3239);

Monochromatic scale

Palettes built from #2f3939

Shades — darker

Tints — lighter

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.

#2f3939 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
BackgroundsBordersBody textDividers
Print note

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

#2f3939, answered

What color is #2f3939?

#2f3939 is a deep muted cyan, closest to Dark Slate Gray (ΔE2000 9.6). It sits at 180° on the hue wheel with 10% saturation and 20% lightness, which reads as cool.

What is the RGB value of #2f3939?

rgb(47, 57, 57) — 47 red, 57 green and 57 blue out of 255, or 18.4% / 22.4% / 22.4% by channel.

Is #2f3939 a light or a dark color?

It is a dark color. Relative luminance is 0.0383 and perceived brightness is 21%, so white text on it reaches 11.90:1.

Should I use black or white text on #2f3939?

White. It scores 11.90:1 against #2f3939, versus 1.77:1 for black — AAA at any size.

What is the complementary color of #2f3939?

#392F2F sits directly opposite on the wheel. Softer options are the split-complements #392F34 and #39342F, which give the same contrast with far less vibration.

What colors go well with #2f3939?

For interface work: #F7F8F8 as the surface, #D2DADA for borders, #687E7E for secondary text, #3B2D30 as an accent and #3A4646 for hover and pressed states. For a palette, the analogous pair #2F3934 and #2F3439 stays calm, while #392F2F is the loudest partner.

What is #2f3939 in CMYK for printing?

cmyk(18%, 0%, 0%, 78%). This is a screen-to-ink approximation — ask your printer for a proof before committing to a run.

Is #2f3939 warm or cool?

Cool — it scores 60 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #413831; nudged cooler, #282F35.

Work with #2f3939 in the Color Lab