What color is #155166?

#155166 is a dark cyan-blue. In RGB it is rgb(21, 81, 102), and in HSL hsl(196, 66%, 24%).

Is #155166 accessible as text?

On white, #155166 has a contrast ratio of 8.75:1 (passes WCAG AA for body text); on black it is 2.40:1 (fails). For text placed on #155166, use white for the best readability.

What is the closest Tailwind color to #155166?

The nearest Tailwind CSS token is cyan-900 (#104E64).

What colors go well with #155166?

#155166 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #662A15. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #155166 below.

Is #155166 good for buttons?

#155166 works well for buttons and highlights, but use white text on #155166 — black text only reaches 2.40:1, below the 4.5:1 needed for normal-size labels.

Is #155166 the same as CSS darkslategray?

No — #155166 is not the CSS named color darkslategray, but darkslategray (#2F4F4F) is the closest CSS named color.

#155166 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #155166

Not just a swatch — here's how #155166 works with other colors. Named schemes with #155166 in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #155166 Accent #A6C4BF Surface #DEDABF Secondary #9AA0A0 Anchor #1E344A

Dark Slate Gray opens this coastal palette with sea-glass and warm sand alongside it, grounded by driftwood grey and a deep-navy anchor.

Nordic Calm Accent · 5 colors

Accent #155166 Secondary #AEB4B8 Surface #F1F2F0 Support #7B93A5 Anchor #2E3236

Dark Slate Gray keeps this Nordic scheme quiet — cool greys and a soft white around it, a muted-blue support and a charcoal anchor.

Tech Product Signal · 5 colors

Signal #155166 Surface #14161A Highlight #F4F6F8 Secondary #596672 Accent #417386

Dark Slate Gray is the vivid signal in this product UI — on a near-black surface with cool white, a slate grey and a lighter tint of Dark Slate Gray.

Vintage Leather Lead · 5 colors

Lead #155166 Secondary #6F5116 Surface #E2DCC0 Accent #385244 Anchor #56233D

Dark Slate Gray plays the worn-leather lead, deepened by saddle brown and an oxblood anchor, softened by aged cream and cooled by a muted forest green.

Minimal Editorial Surface · 5 colors

Surface #F6F4EF Accent #155166 Secondary #63747C Support #969386 Ink #16140F

Dark Slate Gray is the single accent in this high-contrast editorial system — set on near-white paper against near-black ink, with a warm grey and a desaturated tint of Dark Slate Gray carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #155166 actually behaves in design work — read from its OKLCH lightness, chroma and hue, not just its raw numbers. Ten signals to help you decide where this color earns its place.

Warmth 30/100

Cool

Reads cool and recessive — calming, technical, good for trust-led UI.

Softness 38/100

Low

Middle-weight — neither delicate nor heavy.

Depth 58/100

Moderate

Mid depth — usable as an accent or a muted ground.

Naturalness 1/100

Very low

Reads engineered rather than organic — synthetic, digital.

Vintage feel 42/100

Moderate

A faint retro warmth without tipping into sepia.

Luxury 62/100

High

Restrained and premium — deep, quiet, high-end packaging and fashion.

Brand distinctiveness 19/100

Very low

Quiet and neutral — a supporting tone, not a signature.

UI accent fit 62/100

High

Strong interactive accent — visible and can carry a legible label.

Surface fit 38/100

Low

Usable as a tinted surface in measured doses.

Print safety 82/100

Very high

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #155166

For UI

For branding

For interior

For fashion

People also use #155166 with

Sea Green Midnight Blue Wine Red Platinum Dark Slate Gray

UI roles & guardrails

Primary action Safe as a filled button with white label. AAA

Body text Passes on white at 16px and above. Pass

Large display Fine for headings 24px+ on white. Pass

Background Pair with white text at 8.7:1. Use

Subtle surface Use #C6E1EB for cards and hover fills. Tint 80

Avoid beside #153566 — the hue gap is too small to read as intentional. Clash

In real applications

Not a swatch to memorise — a color to build with. Here is #155166 at work across the surfaces designers actually ship.

Website / UI

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Dashboard

Revenue

$48.2k ▲ 12%

Brand

AVELINE

Studio

Poster

Nov 14 · 8PM

NIGHT
MARKET

Packaging

BLOOM

Botanical Wash

250 ml

Interior

Every model

Export

:root {
  --color-base: #155166;
  --color-base-rgb: 21 81 102;
  --color-base-oklch: oklch(40.8% 0.069 226.1);
  --color-50: #F2FAFD;
  --color-100: #DCF1F9;
  --color-200: #BBE3F1;
  --color-300: #8DCBE2;
  --color-400: #62B2D0;
  --color-500: #4096B5;
  --color-600: #38748A;
  --color-700: #2D5462;
  --color-800: #213840;
  --color-900: #162328;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  dark-slate-gray: {
    50: '#F2FAFD',
    100: '#DCF1F9',
    200: '#BBE3F1',
    300: '#8DCBE2',
    400: '#62B2D0',
    500: '#4096B5',
    600: '#38748A',
    700: '#2D5462',
    800: '#213840',
    900: '#162328',
  },
}

$base: #155166;
$base-ink: #FFFFFF;
$base-50: #F2FAFD;
$base-100: #DCF1F9;
$base-200: #BBE3F1;
$base-300: #8DCBE2;
$base-400: #62B2D0;
$base-500: #4096B5;
$base-600: #38748A;
$base-700: #2D5462;
$base-800: #213840;
$base-900: #162328;
$base-hover: #114051;
$base-subtle: #A8D2E2;

{
    "color": {
        "base": {
            "value": "#155166",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F2FAFD",
                "type": "color"
            },
            "100": {
                "value": "#DCF1F9",
                "type": "color"
            },
            "200": {
                "value": "#BBE3F1",
                "type": "color"
            },
            "300": {
                "value": "#8DCBE2",
                "type": "color"
            },
            "400": {
                "value": "#62B2D0",
                "type": "color"
            },
            "500": {
                "value": "#4096B5",
                "type": "color"
            },
            "600": {
                "value": "#38748A",
                "type": "color"
            },
            "700": {
                "value": "#2D5462",
                "type": "color"
            },
            "800": {
                "value": "#213840",
                "type": "color"
            },
            "900": {
                "value": "#162328",
                "type": "color"
            }
        }
    }
}