What color is #423BBF?

#423BBF is a medium blue-violet. In RGB it is rgb(66, 59, 191), and in HSL hsl(243, 53%, 49%).

Is #423BBF accessible as text?

On white, #423BBF has a contrast ratio of 8.05:1 (passes WCAG AA for body text); on black it is 2.61:1 (fails). For text placed on #423BBF, use white for the best readability.

What is the closest Tailwind color to #423BBF?

The nearest Tailwind CSS token is indigo-700 (#432DD7).

What colors go well with #423BBF?

#423BBF pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #B9BF3B. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #423BBF below.

Is #423BBF good for buttons?

#423BBF works well for buttons and highlights, but use white text on #423BBF — black text only reaches 2.61:1, below the 4.5:1 needed for normal-size labels.

Is #423BBF the same as CSS darkslateblue?

No — #423BBF is not the CSS named color darkslateblue, but darkslateblue (#483D8B) is the closest CSS named color.

#423BBF Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #423BBF

Not just a swatch — here's how #423BBF works with other colors. Named schemes with #423BBF in its natural role, and a note on why the supporting colors balance it.

Tech Product Signal · 5 colors

Signal #423BBF Surface #14161A Highlight #F4F6F8 Secondary #5B6672 Accent #6166DD

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

Berry & Cream Lead · 5 colors

Lead #423BBF Surface #F6E5D8 Anchor #5B2142 Accent #E5C2C9 Secondary #322B2F

Cerulean 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 #423BBF Secondary #737AA7 Support #9D9088 Ink #18140F

Cerulean 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 Cerulean carrying the quiet middle.

Coastal Morning Lead · 5 colors

Lead #423BBF Accent #A5C4C2 Surface #EAD5BF Secondary #9AA0A1 Anchor #22344A

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

Sunset Warmth Glow · 5 colors

Glow #423BBF Secondary #E86A71 Accent #F6934E Anchor #583B57 Surface #F7E7D7

Cerulean glows at the center of this sunset palette, joined by coral and gold, deepened by a plum anchor and cooled with cream.

Build a working theme in the generator →

Color Lab

How #423BBF 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 16/100

Cool

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

Softness 29/100

Low

Firm and assertive — carries weight and contrast.

Depth 59/100

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 23/100

Low

Clean and current — no dusty, aged cast.

Luxury 55/100

Moderate

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

Brand distinctiveness 76/100

High

Bold and ownable — memorable as a primary brand color.

UI accent fit 78/100

High

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

Surface fit 11/100

Very low

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

Print safety 69/100

High

Prints close, with a slight loss of vibrancy.

Pairs with #423BBF

For UI

For branding

For interior

For fashion

People also use #423BBF with

Ocean Blue Dark Orchid Peridot Gainsboro Prussian Blue

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 8.0:1. Use

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

Avoid beside #6D3BBF — 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 #423BBF 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: #423BBF;
  --color-base-rgb: 66 59 191;
  --color-base-oklch: oklch(45.0% 0.198 277.2);
  --color-50: #F3F3FC;
  --color-100: #E0DFF6;
  --color-200: #C3C1EC;
  --color-300: #9995DA;
  --color-400: #726DC5;
  --color-500: #504CA9;
  --color-600: #434082;
  --color-700: #34325D;
  --color-800: #25243D;
  --color-900: #181726;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  cerulean: {
    50: '#F3F3FC',
    100: '#E0DFF6',
    200: '#C3C1EC',
    300: '#9995DA',
    400: '#726DC5',
    500: '#504CA9',
    600: '#434082',
    700: '#34325D',
    800: '#25243D',
    900: '#181726',
  },
}

$base: #423BBF;
$base-ink: #FFFFFF;
$base-50: #F3F3FC;
$base-100: #E0DFF6;
$base-200: #C3C1EC;
$base-300: #9995DA;
$base-400: #726DC5;
$base-500: #504CA9;
$base-600: #434082;
$base-700: #34325D;
$base-800: #25243D;
$base-900: #181726;
$base-hover: #342F99;
$base-subtle: #CAC8E8;

{
    "color": {
        "base": {
            "value": "#423BBF",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F3F3FC",
                "type": "color"
            },
            "100": {
                "value": "#E0DFF6",
                "type": "color"
            },
            "200": {
                "value": "#C3C1EC",
                "type": "color"
            },
            "300": {
                "value": "#9995DA",
                "type": "color"
            },
            "400": {
                "value": "#726DC5",
                "type": "color"
            },
            "500": {
                "value": "#504CA9",
                "type": "color"
            },
            "600": {
                "value": "#434082",
                "type": "color"
            },
            "700": {
                "value": "#34325D",
                "type": "color"
            },
            "800": {
                "value": "#25243D",
                "type": "color"
            },
            "900": {
                "value": "#181726",
                "type": "color"
            }
        }
    }
}

Palettes built on #423BBF

Color Lab

Pairs with #423BBF

UI roles & guardrails

In real applications

Scales

Every model

Export