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cyan · cool

#3b686f

a dark, soft cyan · cool · closest name: Dark Slate Gray

Token name suggestion: Slate Lagoon

RGB
59, 104, 111
HSL
188°, 31%, 33%
CMYK
47, 6, 0, 57
Luminance
0.1198

#3b686f is a dark soft cyan, 188° on the wheel and 86/100 on the cool side. Put white text on it (6.18:1). As text it scores 6.18:1 on white — safe at any size. Nearest name is Dark Slate Gray, nearest Tailwind family is slate.

hsl(188 31% 33%)rgb(59 104 111)Base step 800AA inkCool

At a glance

Every number on this page in one read: what #3b686f is made of, how bright it looks, and which way it leans.

Hex
#3b686f
Hue
188°
cyan
Saturation
31%
soft
Lightness
33%
dark
Brightness
44%
HSV value
Perceived
37%
weighted brightness
Luminance
0.1198
WCAG relative
Temperature
Cool
86/100 cool
Color family
Cyan
Tone
Soft
Best ink
White
6.18:1
Closest name
Dark Slate Gray
ΔE2000 9.1
Chroma
16.1
LCH, 0–130ish
OKLCH L
0.488
perceptual lightness
Tailwind
slate
500 · ΔE 15.1
Web-safe
#336666
nearest of 216
Where it sits
Hue188° of 360°
Saturation31%
Lightness33%
Saturation × lightness field

Left edge is grey, right edge is full chroma; top is white, bottom is black. The dot is #3b686f.

Temperature
Warm ← → Cool86% 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
Red8%
Green83%
Blue10%

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

Every format

HEX#3b686f
HEX (8-digit)#3b686fff
RGBrgb(59, 104, 111)
RGBArgba(59, 104, 111, 1)
HSLhsl(188, 31%, 33%)
HSV / HSBhsv(188, 47%, 44%)
HWBhwb(188 23% 56%)
CMYKcmyk(47%, 6%, 0%, 57%)
LABlab(41.2 -13.4 -8.8)
LCHlch(41.2 16.1 213.1)
OKLCHoklch(0.488 0.051 208.4)
XYZ (D65)xyz(9.62, 11.98, 16.84)
Decimal3893359
Display P3color(display-p3 0.231 0.408 0.435)
Web-safe#336666

Copy-ready code

every platformclick to select
/* CSS */
color: #3b686f;
background-color: #3b686f;
/* CSS custom property */
--brand: #3b686f;
/* Tailwind (arbitrary) */
class="text-[#3b686f] bg-[#3b686f]"
/* SCSS */
$brand: #3b686f;
/* SwiftUI */
Color(red: 0.231, green: 0.408, blue: 0.435)
/* UIKit */
UIColor(red: 0.231, green: 0.408, blue: 0.435, alpha: 1)
/* Android XML */
<color name="brand">#3B686F</color>
/* Android Compose */
Color(0xFF3B686F)
/* Flutter */
Color(0xFF3B686F)
/* Python / OpenCV (BGR) */
(111, 104, 59)
/* Python / PIL (RGB) */
(59, 104, 111)
/* Java AWT */
new Color(59, 104, 111)
/* .NET */
Color.FromArgb(255, 59, 104, 111)
/* OpenGL / Unity (0–1) */
(0.2314f, 0.4078f, 0.4353f, 1f)
/* LaTeX */
\definecolor{brand}{RGB}{59,104,111}
modern cssclick to select
/* mix without leaving CSS */
background: color-mix(in oklab, #3b686f 85%, white);
border-color: color-mix(in oklab, #3b686f 40%, transparent);
/* theme-aware in one line */
color: light-dark(#2C4E53, #D7E7EA);
/* relative colour syntax */
--hover: hsl(from #3b686f 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: #F6F9F9;
  --brand-100: #ECF2F3;
  --brand-200: #D5E4E7;
  --brand-300: #B6D3D8;
  --brand-400: #91BEC5;
  --brand-500: #6CA8B1;
  --brand-600: #5596A0;
  --brand-700: #477D85;
  --brand-800: #3b686f;
  --brand-900: #2C4A4E;
  --brand-950: #1B2E31;
  --brand: #3b686f;
  --brand-ink: #ffffff;
  --brand-surface: #F5F9FA;
  --brand-border: #CADFE3;
  --brand-hover: #2F5258;
  --brand-pressed: #223C40;
}
@media (prefers-color-scheme: dark) {
  :root {
    --brand-surface: #142224;
    --brand-ink: #D7E7EA;
  }
}
tailwind.config.jsclick to select
theme: {
  extend: {
    colors: {
      brand: {
        50: '#F6F9F9',
        100: '#ECF2F3',
        200: '#D5E4E7',
        300: '#B6D3D8',
        400: '#91BEC5',
        500: '#6CA8B1',
        600: '#5596A0',
        700: '#477D85',
        800: '#3b686f',
        900: '#2C4A4E',
        950: '#1B2E31',
        DEFAULT: '#3b686f',
      },
    },
  },
}
scss mapclick to select
$brand: (
  '50': #F6F9F9,
  '100': #ECF2F3,
  '200': #D5E4E7,
  '300': #B6D3D8,
  '400': #91BEC5,
  '500': #6CA8B1,
  '600': #5596A0,
  '700': #477D85,
  '800': #3b686f,
  '900': #2C4A4E,
  '950': #1B2E31,
);
$brand-base: #3b686f;
$brand-ink: #ffffff;

@function brand($step) { @return map-get($brand, $step); }
w3c design tokens (json)click to select
{
  "color": {
    "brand": {
      "50": { "$value": "#F6F9F9", "$type": "color" },
      "100": { "$value": "#ECF2F3", "$type": "color" },
      "200": { "$value": "#D5E4E7", "$type": "color" },
      "300": { "$value": "#B6D3D8", "$type": "color" },
      "400": { "$value": "#91BEC5", "$type": "color" },
      "500": { "$value": "#6CA8B1", "$type": "color" },
      "600": { "$value": "#5596A0", "$type": "color" },
      "700": { "$value": "#477D85", "$type": "color" },
      "800": { "$value": "#3b686f", "$type": "color" },
      "900": { "$value": "#2C4A4E", "$type": "color" },
      "950": { "$value": "#1B2E31", "$type": "color" }
    },
    "brandInk": { "$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 #3b686f · 6.18:1
Use #ffffffAA at every size, AAA for large text only.
Aa
12px
Aa
16px
Aa
24px
Aa
White text · 6.18:1 · recommended
AA pass · AA large pass · AAA fail
Aa
Black text · 3.40:1
AA fail · AA large pass · AAA fail
Reading the other direction: #3b686f as text scores 6.18:1 on white and 3.40:1 on black.
Best tinted ink on it, if plain black or white feels flat: #EEF5F6 at 5.60:1.

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
#3b686f · 6.18:1
AA on whitealready passes
#3b686f
The quick fox
#365F65 · 7.04:1
AAA on white−3% L
#365F65
The quick fox
#477E86 · 4.60:1
AA on black+7% L
#477E86
The quick fox
#5D9FA9 · 7.00:1
AAA on black+18% L
#5D9FA9

Large text — 24px regular or 18.66px bold and above — only needs 3:1, so #3B686F 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
#3b686f on white: 6.18:1
AA ✓ pass · AA-large · AAA
Aa
#3b686f on black: 3.40:1
AA ✗ fail · AA-large · AAA
Against the neutral ladder

Contrast is symmetric, so each row covers both directions: #3b686f as text on that neutral, and that neutral as text on #3b686f.

NeutralRatioBoth directions
White6.18:1AaAa
Slate 505.91:1AaAa
Slate 1005.65:1AaAa
Slate 2005.02:1AaAa
Slate 3004.17:1AaAa
Slate 4002.41:1AaAa
Slate 5001.30:1AaAa
Slate 6001.23:1AaAa
Slate 7001.67:1AaAa
Slate 8002.37:1AaAa
Slate 9002.89:1AaAa
Black3.40:1AaAa
Colour vision deficiency
true color
protanopia · #61656F
deuteranopia · #595E6F
tritanopia · #226C6A

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. #3b686f is pinned to step 800; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F6F9F9
#ECF2F3
#D5E4E7
#B6D3D8
#91BEC5
#6CA8B1
#5596A0
#477D85
#3b686f
#2C4A4E
#1B2E31
Base = 800Lightest = 50 · #F6F9F9Darkest = 950 · #1B2E31Text 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 0.013 208.4);
  --brand-100: oklch(0.94 0.020 208.4);
  --brand-200: oklch(0.88 0.030 208.4);
  --brand-300: oklch(0.80 0.040 208.4);
  --brand-400: oklch(0.72 0.047 208.4);
  --brand-500: oklch(0.64 0.051 208.4);
  --brand-600: oklch(0.56 0.051 208.4);
  --brand-700: oklch(0.48 0.048 208.4);
  --brand-800: oklch(0.40 0.043 208.4);
  --brand-900: oklch(0.32 0.036 208.4);
  --brand-950: oklch(0.24 0.028 208.4);
}

Colors that work with #3b686f

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#F5F9FA
Tinted page background
Border#CADFE3
Hairlines and dividers
Muted text#508C96
Captions on the surface
Accent#72383E
Second voice, not a rival
Dark variant#2C4E53
Hover, pressed, headers
Light variant#EEF5F6
Selected rows, tints
Dark surface#142224
Dark-mode background
Hover#2F5258
One step down in lightness
Pressed#223C40
Two steps down
Disabled#749FA6
Chroma pulled out
Focus ring#387B86
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 #3b686f

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
  • 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
  • Weight67/100
  • 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#6F423B
Analogous left#3B6F5C
Analogous right#3B4E6F
Split-complement 1#6F3B4E
Split-complement 2#6F5C3B
Triadic 1#6F3B68
Triadic 2#686F3B
Tetradic#5C3B6F
On the wheel
Base+30°−30°+120°+240°+180°188°

#3b686f sits at 188°. Every dot is a harmony position and links to its own page in the table alongside.

RGB percentages

Red23.1%
Green40.8%
Blue43.5%
R · 0–255
59
0x3b
G · 0–255
104
0x68
B · 0–255
111
0x6f

CMYK percentages

Cyan46.8%
Magenta6.3%
Yellow0.0%
Key (black)56.5%

Total ink coverage is 110%. Most commercial presses cap around 300% — above that, sheets stop drying properly.

Color previews

#3b686f text on a black background

contrast 3.40:1

Card sample

#3b686f text on a white background

contrast 6.18:1

Card sample

#3b686f on grey

5.65:1

#3b686f on its own surface

5.83:1

#3b686f on its dark surface

2.64:1

CSS3 live lab

Text font color

The quick brown fox

color: #3b686f;
Background color
Panel with #3b686f background
background-color: #3b686f;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #3b686f;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(59, 104, 111, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(59, 104, 111, 0.45);
Border & gradient
Gradient panel
border: 3px solid #3b686f;
background: linear-gradient(135deg, #3b686f, #3B456F);
Gradient text

Gradient headline

background: linear-gradient(90deg, #3b686f, #3E3B6F);
-webkit-background-clip: text;
color: transparent;
Focus ring
Focused control
outline: 2px solid #3b686f;
outline-offset: 3px;
Underline & caret

Marked up text

text-decoration-color: #3b686f;
caret-color: #3b686f;
Left rule
Pull quote or callout
border-left: 4px solid #3b686f;
Ring + tint
Selected chip
background: #EEF5F6;
box-shadow: inset 0 0 0 2px #3b686f;
Conic badge
68%
background: conic-gradient(#3b686f 68%, #e2e8f0 0);

Transparency

What each alpha value actually composites to. The top row is #3b686f 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(59, 104, 111, 0.5)
rgb(59 104 111 / 50%)
#3b686f80
hsl(188 31% 33% / 50%)
color-mix(in srgb, #3b686f 50%, transparent)
Alpha8-digit hexFlat on white
10%#3b686f1a#EBF0F1
20%#3b686f33#D8E1E2
40%#3b686f66#B1C3C5
60%#3b686f99#89A4A9
80%#3b686fcc#62868C

Gradients from #3b686f

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, #508D97, #3b686f 45%, #2C4E53);
Duotone
A short hue run reads richer than a flat fill
background: linear-gradient(120deg, #3b686f, #30355B);
Complement sweep
Loud — keep it behind large type only
background: linear-gradient(90deg, #3b686f, #6F423B);
Spotlight
Hero panels and app headers
background: radial-gradient(120% 120% at 20% 0%, #5D9FA9 0%, #3b686f 45%, #2C4E53 100%);
Soft wash
Section backgrounds that stay readable
background: linear-gradient(180deg, #F5F9FA, #ffffff);
Mesh
Ambient background, no image weight
background: radial-gradient(60% 60% at 15% 20%, #4D9072 0%, transparent 60%), radial-gradient(55% 55% at 85% 15%, #465783 0%, transparent 60%), radial-gradient(70% 70% at 50% 95%, #2C4E53 0%, transparent 65%), #3b686f;

Monochromatic scale

Palettes built from #3b686f

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.

#3b686f 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

Holds up across typical panel gamma. Still worth checking on an uncalibrated laptop, where mid-tones shift most.

In dark mode

Too dim on dark surfaces at 3.40:1 — lift it to #477E86 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.

#3b686f, answered

What color is #3b686f?

#3b686f is a dark soft cyan, closest to Dark Slate Gray (ΔE2000 9.1). It sits at 188° on the hue wheel with 31% saturation and 33% lightness, which reads as cool.

What is the RGB value of #3b686f?

rgb(59, 104, 111) — 59 red, 104 green and 111 blue out of 255, or 23.1% / 40.8% / 43.5% by channel.

What is #3b686f in HSL and HSV?

hsl(188, 31%, 33%) and hsv(188, 47%, 44%). HSL is what CSS takes; HSV is what your design tool's picker shows, which is why the saturation numbers rarely match.

Is #3b686f a light or a dark color?

It is a dark color. Relative luminance is 0.1198 and perceived brightness is 37%, so white text on it reaches 6.18:1.

Should I use black or white text on #3b686f?

White. It scores 6.18:1 against #3b686f, versus 3.40:1 for black — AA at any size.

Is #3b686f accessible on a white background?

#3b686f on white scores 6.18:1, which clears AA at every size but not AAA.

What is the complementary color of #3b686f?

#6F423B sits directly opposite on the wheel. Softer options are the split-complements #6F3B4E and #6F5C3B, which give the same contrast with far less vibration.

What colors go well with #3b686f?

For interface work: #F5F9FA as the surface, #CADFE3 for borders, #508C96 for secondary text, #72383E as an accent and #2C4E53 for hover and pressed states. For a palette, the analogous pair #3B6F5C and #3B4E6F stays calm, while #6F423B is the loudest partner.

What is #3b686f in CMYK for printing?

cmyk(47%, 6%, 0%, 57%). This is a screen-to-ink approximation — ask your printer for a proof before committing to a run.

Is #3b686f warm or cool?

Cool — it scores 86 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #3B6F63; nudged cooler, #395871.

Which Tailwind color is closest to #3b686f?

The slate family — its 500 step is #64748b, ΔE2000 15.1 away. That is a visible difference, so define #3b686f as a custom token rather than reaching for the built-in.

How do I use #3b686f in Tailwind CSS?

Inline it as an arbitrary value with bg-[#3b686f] or text-[#3b686f], 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 #3b686f with 50% opacity?

rgba(59, 104, 111, 0.5), or #3b686f80 in eight-digit hex. Over white that composites to #9DB4B7; over black, #1E3438.

Is #3b686f a web-safe color?

No. The nearest web-safe colour is #336666, ΔE2000 4.2 away. The palette only matters for legacy displays and some email clients now.

What does the color #3b686f 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 #3b686f?

The safest is same-hue elevation: linear-gradient(135deg, #508D97, #3b686f 45%, #2C4E53). For more colour, a short hue run to #30355B keeps it rich without turning muddy.

Work with #3b686f in the Color Lab

Every tool opens with this colour already loaded.

Every value on this page is computed from #3b686f at request time — conversions, contrast ratios and ΔE distances are calculated, never looked up.