What color is #5666BC?

#5666BC is a medium blue-violet. In RGB it is rgb(86, 102, 188), and in HSL hsl(231, 43%, 54%).

Is #5666BC accessible as text?

On white, #5666BC has a contrast ratio of 5.22:1 (passes WCAG AA for body text); on black it is 4.02:1 (fails). For text placed on #5666BC, use white for the best readability.

What is the closest Tailwind color to #5666BC?

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

What colors go well with #5666BC?

#5666BC pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #BCAD57. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #5666BC below.

Is #5666BC good for buttons?

#5666BC works well for buttons and highlights, but use white text on #5666BC — black text only reaches 4.02:1, below the 4.5:1 needed for normal-size labels.

Is #5666BC the same as CSS slateblue?

No — #5666BC is not the CSS named color slateblue, but slateblue (#6A5ACD) is the closest CSS named color.

#5666BC Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #5666BC

Not just a swatch — here's how #5666BC works with other colors. Named schemes with #5666BC in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #5666BC Accent #A5C4C2 Surface #EAD5C0 Secondary #9AA0A1 Anchor #21344A

Tanzanite 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 #5666BC Surface #14161A Highlight #F4F6F8 Secondary #5B6672 Accent #7A8CDC

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

Vintage Leather Lead · 5 colors

Lead #5666BC Secondary #7F4535 Surface #EED7C2 Accent #365247 Anchor #582239

Tanzanite 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 #5666BC Surface #F6E5D8 Anchor #5B2143 Accent #E5C2C9 Secondary #322B2F

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

Minimal Editorial Surface · 5 colors

Surface #F8F4EF Accent #5666BC Secondary #8E97B6 Support #9D8F88 Ink #18140F

Tanzanite 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 Tanzanite carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #5666BC 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 21/100

Cool

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

Softness 42/100

Moderate

Middle-weight — neither delicate nor heavy.

Depth 47/100

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 48/100

Moderate

A faint retro warmth without tipping into sepia.

Luxury 52/100

Moderate

Understated — leans refined without going austere.

Brand distinctiveness 36/100

Low

Recognisable but shares space with nearby hues.

UI accent fit 100/100

Very high

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

Surface fit 15/100

Very low

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

Print safety 78/100

High

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #5666BC

For UI

For branding

For interior

For fashion

People also use #5666BC with

Iceberg Royal Purple Brass Gainsboro Prussian Blue

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 5.2:1. Use

Subtle surface Use #E0E2EF for cards and hover fills. Tint 80

Avoid beside #6A57BC — 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 #5666BC 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: #5666BC;
  --color-base-rgb: 86 102 188;
  --color-base-oklch: oklch(54.0% 0.135 273.1);
  --color-50: #F4F5FB;
  --color-100: #E1E4F4;
  --color-200: #C5CAE8;
  --color-300: #9CA4D3;
  --color-400: #7580BD;
  --color-500: #5560A0;
  --color-600: #464E7C;
  --color-700: #363B59;
  --color-800: #26293B;
  --color-900: #191B24;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  tanzanite: {
    50: '#F4F5FB',
    100: '#E1E4F4',
    200: '#C5CAE8',
    300: '#9CA4D3',
    400: '#7580BD',
    500: '#5560A0',
    600: '#464E7C',
    700: '#363B59',
    800: '#26293B',
    900: '#191B24',
  },
}

$base: #5666BC;
$base-ink: #FFFFFF;
$base-50: #F4F5FB;
$base-100: #E1E4F4;
$base-200: #C5CAE8;
$base-300: #9CA4D3;
$base-400: #7580BD;
$base-500: #5560A0;
$base-600: #464E7C;
$base-700: #363B59;
$base-800: #26293B;
$base-900: #191B24;
$base-hover: #3F4D9E;
$base-subtle: #D0D4E7;

{
    "color": {
        "base": {
            "value": "#5666BC",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F4F5FB",
                "type": "color"
            },
            "100": {
                "value": "#E1E4F4",
                "type": "color"
            },
            "200": {
                "value": "#C5CAE8",
                "type": "color"
            },
            "300": {
                "value": "#9CA4D3",
                "type": "color"
            },
            "400": {
                "value": "#7580BD",
                "type": "color"
            },
            "500": {
                "value": "#5560A0",
                "type": "color"
            },
            "600": {
                "value": "#464E7C",
                "type": "color"
            },
            "700": {
                "value": "#363B59",
                "type": "color"
            },
            "800": {
                "value": "#26293B",
                "type": "color"
            },
            "900": {
                "value": "#191B24",
                "type": "color"
            }
        }
    }
}

Palettes built on #5666BC

Color Lab

Pairs with #5666BC

UI roles & guardrails

In real applications

Scales

Every model

Export