What color is #03556B?

#03556B is a dark, vivid cyan. In RGB it is rgb(3, 85, 107), and in HSL hsl(193, 95%, 22%).

Is #03556B accessible as text?

On white, #03556B has a contrast ratio of 8.35:1 (passes WCAG AA for body text); on black it is 2.52:1 (fails). For text placed on #03556B, use white for the best readability.

What is the closest Tailwind color to #03556B?

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

What colors go well with #03556B?

#03556B pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #6D1A03. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #03556B below.

Is #03556B good for buttons?

#03556B works well for buttons and highlights, but use white text on #03556B — black text only reaches 2.52:1, below the 4.5:1 needed for normal-size labels.

Is #03556B the same as CSS darkslategray?

No — #03556B is not the CSS named color darkslategray, but darkslategray (#2F4F4F) is the closest CSS named color.

#03556B Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #03556B

Not just a swatch — here's how #03556B works with other colors. Named schemes with #03556B in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #03556B 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 #03556B 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 #03556B Surface #14161A Highlight #F4F6F8 Secondary #596672 Accent #3C778C

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 #03556B Secondary #6F5116 Surface #E2DCC0 Accent #385244 Anchor #56233E

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 #03556B Secondary #637880 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 #03556B 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 27/100

Cool

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

Softness 38/100

Low

Middle-weight — neither delicate nor heavy.

Depth 57/100

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 45/100

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 21/100

Low

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

UI accent fit 68/100

High

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

Surface fit 34/100

Low

Usable as a tinted surface in measured doses.

Print safety 79/100

High

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #03556B

For UI

For branding

For interior

For fashion

People also use #03556B with

Shamrock Green Midnight Blue Rosewood 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 8.3:1. Use

Subtle surface Use #BCE7F2 for cards and hover fills. Tint 80

Avoid beside #03336D — 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 #03556B 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: #03556B;
  --color-base-rgb: 3 85 107;
  --color-base-oklch: oklch(41.8% 0.077 223.4);
  --color-50: #F0FBFE;
  --color-100: #D8F5FD;
  --color-200: #B1EBFC;
  --color-300: #7ADAF5;
  --color-400: #4AC6E8;
  --color-500: #27AACE;
  --color-600: #26829C;
  --color-700: #215D6E;
  --color-800: #1A3D47;
  --color-900: #12262B;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  dark-slate-gray: {
    50: '#F0FBFE',
    100: '#D8F5FD',
    200: '#B1EBFC',
    300: '#7ADAF5',
    400: '#4AC6E8',
    500: '#27AACE',
    600: '#26829C',
    700: '#215D6E',
    800: '#1A3D47',
    900: '#12262B',
  },
}

$base: #03556B;
$base-ink: #FFFFFF;
$base-50: #F0FBFE;
$base-100: #D8F5FD;
$base-200: #B1EBFC;
$base-300: #7ADAF5;
$base-400: #4AC6E8;
$base-500: #27AACE;
$base-600: #26829C;
$base-700: #215D6E;
$base-800: #1A3D47;
$base-900: #12262B;
$base-hover: #024558;
$base-subtle: #98DCEE;

{
    "color": {
        "base": {
            "value": "#03556B",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F0FBFE",
                "type": "color"
            },
            "100": {
                "value": "#D8F5FD",
                "type": "color"
            },
            "200": {
                "value": "#B1EBFC",
                "type": "color"
            },
            "300": {
                "value": "#7ADAF5",
                "type": "color"
            },
            "400": {
                "value": "#4AC6E8",
                "type": "color"
            },
            "500": {
                "value": "#27AACE",
                "type": "color"
            },
            "600": {
                "value": "#26829C",
                "type": "color"
            },
            "700": {
                "value": "#215D6E",
                "type": "color"
            },
            "800": {
                "value": "#1A3D47",
                "type": "color"
            },
            "900": {
                "value": "#12262B",
                "type": "color"
            }
        }
    }
}

Palettes built on #03556B

Color Lab

Pairs with #03556B

UI roles & guardrails

In real applications

Scales

Every model

Export