What color is #1666BB?

#1666BB is a medium, vivid blue. In RGB it is rgb(22, 102, 187), and in HSL hsl(211, 79%, 41%).

Is #1666BB accessible as text?

On white, #1666BB has a contrast ratio of 5.75:1 (passes WCAG AA for body text); on black it is 3.65:1 (fails). For text placed on #1666BB, use white for the best readability.

What is the closest Tailwind color to #1666BB?

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

What colors go well with #1666BB?

#1666BB pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #BB6B16. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #1666BB below.

Is #1666BB good for buttons?

#1666BB works well for buttons and highlights, but use white text on #1666BB — black text only reaches 3.65:1, below the 4.5:1 needed for normal-size labels.

Is #1666BB the same as CSS royalblue?

No — #1666BB is not the CSS named color royalblue, but royalblue (#4169E1) is the closest CSS named color.

#1666BB Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #1666BB

Not just a swatch — here's how #1666BB works with other colors. Named schemes with #1666BB in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #1666BB Accent #A5C4C1 Surface #DDDBBF Secondary #9AA0A1 Anchor #20344A

Denim Blue 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 #1666BB Surface #14161A Highlight #F4F6F8 Secondary #5A6672 Accent #4A8CDB

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

Vintage Leather Lead · 5 colors

Lead #1666BB Secondary #7F4537 Surface #E1DDC1 Accent #375246 Anchor #57233B

Denim Blue 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 #1666BB Surface #EDE9D6 Anchor #5A2145 Accent #E4C2CB Secondary #322B2F

Denim Blue 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 #1666BB Secondary #7A92B0 Support #9D8F89 Ink #16140F

Denim Blue 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 Denim Blue carrying the quiet middle.

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Color Lab

How #1666BB 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 9/100

Cool

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

Softness 38/100

Low

Middle-weight — neither delicate nor heavy.

Depth 50/100

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 38/100

Low

A faint retro warmth without tipping into sepia.

Luxury 53/100

Moderate

Understated — leans refined without going austere.

Brand distinctiveness 41/100

Moderate

Recognisable but shares space with nearby hues.

UI accent fit 99/100

Very high

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

Surface fit 9/100

Very low

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

Print safety 68/100

High

Prints close, with a slight loss of vibrancy.

Pairs with #1666BB

For UI

For branding

For interior

For fashion

People also use #1666BB with

Turquoise Medium Blue Ginger Gainsboro 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 5.7:1. Use

Subtle surface Use #D0E0F2 for cards and hover fills. Tint 80

Avoid beside #162FBB — 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 #1666BB 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: #1666BB;
  --color-base-rgb: 22 102 187;
  --color-base-oklch: oklch(51.2% 0.152 254.4);
  --color-50: #F1F7FE;
  --color-100: #DAEAFC;
  --color-200: #B6D5F6;
  --color-300: #85B6EB;
  --color-400: #5897DA;
  --color-500: #3578C0;
  --color-600: #305F92;
  --color-700: #284667;
  --color-800: #1D3043;
  --color-900: #141E29;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  denim-blue: {
    50: '#F1F7FE',
    100: '#DAEAFC',
    200: '#B6D5F6',
    300: '#85B6EB',
    400: '#5897DA',
    500: '#3578C0',
    600: '#305F92',
    700: '#284667',
    800: '#1D3043',
    900: '#141E29',
  },
}

$base: #1666BB;
$base-ink: #FFFFFF;
$base-50: #F1F7FE;
$base-100: #DAEAFC;
$base-200: #B6D5F6;
$base-300: #85B6EB;
$base-400: #5897DA;
$base-500: #3578C0;
$base-600: #305F92;
$base-700: #284667;
$base-800: #1D3043;
$base-900: #141E29;
$base-hover: #125196;
$base-subtle: #B7D1ED;

{
    "color": {
        "base": {
            "value": "#1666BB",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F1F7FE",
                "type": "color"
            },
            "100": {
                "value": "#DAEAFC",
                "type": "color"
            },
            "200": {
                "value": "#B6D5F6",
                "type": "color"
            },
            "300": {
                "value": "#85B6EB",
                "type": "color"
            },
            "400": {
                "value": "#5897DA",
                "type": "color"
            },
            "500": {
                "value": "#3578C0",
                "type": "color"
            },
            "600": {
                "value": "#305F92",
                "type": "color"
            },
            "700": {
                "value": "#284667",
                "type": "color"
            },
            "800": {
                "value": "#1D3043",
                "type": "color"
            },
            "900": {
                "value": "#141E29",
                "type": "color"
            }
        }
    }
}

Palettes built on #1666BB

Color Lab

Pairs with #1666BB

UI roles & guardrails

In real applications

Scales

Every model

Export