What color is #0366A8?

#0366A8 is a dark, vivid cyan-blue. In RGB it is rgb(3, 102, 168), and in HSL hsl(204, 96%, 34%).

Is #0366A8 accessible as text?

On white, #0366A8 has a contrast ratio of 6.05:1 (passes WCAG AA for body text); on black it is 3.47:1 (fails). For text placed on #0366A8, use white for the best readability.

What is the closest Tailwind color to #0366A8?

The nearest Tailwind CSS token is sky-700 (#0069A8).

What colors go well with #0366A8?

#0366A8 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #AA4603. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #0366A8 below.

Is #0366A8 good for buttons?

#0366A8 works well for buttons and highlights, but use white text on #0366A8 — black text only reaches 3.47:1, below the 4.5:1 needed for normal-size labels.

Is #0366A8 the same as CSS steelblue?

No — #0366A8 is not the CSS named color steelblue, but steelblue (#4682B4) is the closest CSS named color.

#0366A8 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #0366A8

Not just a swatch — here's how #0366A8 works with other colors. Named schemes with #0366A8 in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #0366A8 Accent #A5C4C0 Surface #DDDBBF Secondary #9AA0A1 Anchor #20344A

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

Tech Product Signal · 5 colors

Signal #0366A8 Surface #14161A Highlight #F4F6F8 Secondary #5A6672 Accent #448AC8

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

Vintage Leather Lead · 5 colors

Lead #0366A8 Secondary #7F4438 Surface #E1DDC0 Accent #375245 Anchor #57233B

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

Berry & Cream Lead · 5 colors

Lead #0366A8 Surface #EDE9D6 Anchor #5A2245 Accent #E4C2CB Secondary #322B2F

Lapis Lazuli sits between cream and a deep berry here, softened by a blush accent and grounded by charcoal.

Minimal Editorial Surface · 5 colors

Surface #F6F4EF Accent #0366A8 Secondary #758EA6 Support #969386 Ink #16140F

Lapis Lazuli 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 Lapis Lazuli carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #0366A8 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 13/100

Cool

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

Softness 39/100

Low

Middle-weight — neither delicate nor heavy.

Depth 51/100

Moderate

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

Naturalness 0/100

Very low

Reads engineered rather than organic — synthetic, digital.

Vintage feel 43/100

Moderate

A faint retro warmth without tipping into sepia.

Luxury 56/100

Moderate

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

Brand distinctiveness 35/100

Low

Recognisable but shares space with nearby hues.

UI accent fit 98/100

Very high

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

Surface fit 13/100

Very low

Too saturated or mid-toned for big areas — keep it to accents.

Print safety 71/100

High

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #0366A8

For UI

For branding

For interior

For fashion

People also use #0366A8 with

Medium Aquamarine Zaffre Brown Platinum Charcoal

UI roles & guardrails

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

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 6.1:1. Use

Subtle surface Use #C6E2F5 for cards and hover fills. Tint 80

Avoid beside #0330AA — 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 #0366A8 at work across the surfaces designers actually ship.

Website / UI

Northwind Sign up

Build faster.

A working theme, generated in seconds.

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: #0366A8;
  --color-base-rgb: 3 102 168;
  --color-base-oklch: oklch(49.7% 0.131 247.4);
  --color-50: #F0F9FE;
  --color-100: #D8EEFD;
  --color-200: #B1DEFC;
  --color-300: #7AC4F6;
  --color-400: #4AA9E8;
  --color-500: #268BCF;
  --color-600: #256D9D;
  --color-700: #214F6E;
  --color-800: #193548;
  --color-900: #12212C;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  lapis-lazuli: {
    50: '#F0F9FE',
    100: '#D8EEFD',
    200: '#B1DEFC',
    300: '#7AC4F6',
    400: '#4AA9E8',
    500: '#268BCF',
    600: '#256D9D',
    700: '#214F6E',
    800: '#193548',
    900: '#12212C',
  },
}

$base: #0366A8;
$base-ink: #FFFFFF;
$base-50: #F0F9FE;
$base-100: #D8EEFD;
$base-200: #B1DEFC;
$base-300: #7AC4F6;
$base-400: #4AA9E8;
$base-500: #268BCF;
$base-600: #256D9D;
$base-700: #214F6E;
$base-800: #193548;
$base-900: #12212C;
$base-hover: #035388;
$base-subtle: #A8D4F1;

{
    "color": {
        "base": {
            "value": "#0366A8",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F0F9FE",
                "type": "color"
            },
            "100": {
                "value": "#D8EEFD",
                "type": "color"
            },
            "200": {
                "value": "#B1DEFC",
                "type": "color"
            },
            "300": {
                "value": "#7AC4F6",
                "type": "color"
            },
            "400": {
                "value": "#4AA9E8",
                "type": "color"
            },
            "500": {
                "value": "#268BCF",
                "type": "color"
            },
            "600": {
                "value": "#256D9D",
                "type": "color"
            },
            "700": {
                "value": "#214F6E",
                "type": "color"
            },
            "800": {
                "value": "#193548",
                "type": "color"
            },
            "900": {
                "value": "#12212C",
                "type": "color"
            }
        }
    }
}

Palettes built on #0366A8

Color Lab

Pairs with #0366A8

UI roles & guardrails

In real applications

Scales

Every model

Export