What color is #424B66?

#424B66 is a dark, muted blue. In RGB it is rgb(66, 75, 102), and in HSL hsl(225, 21%, 33%).

Is #424B66 accessible as text?

On white, #424B66 has a contrast ratio of 8.64:1 (passes WCAG AA for body text); on black it is 2.43:1 (fails). For text placed on #424B66, use white for the best readability.

What is the closest Tailwind color to #424B66?

The nearest Tailwind CSS token is mauve-600 (#594C5B).

What colors go well with #424B66?

#424B66 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #665D42. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #424B66 below.

Is #424B66 good for buttons?

#424B66 works well for buttons and highlights, but use white text on #424B66 — black text only reaches 2.43:1, below the 4.5:1 needed for normal-size labels.

Is #424B66 the same as CSS darkslategray?

No — #424B66 is not the CSS named color darkslategray, but darkslategray (#2F4F4F) is the closest CSS named color.

#424B66 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #424B66

Not just a swatch — here's how #424B66 works with other colors. Named schemes with #424B66 in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #424B66 Accent #A5C4C2 Surface #EAD5C0 Secondary #9AA0A1 Anchor #21344A

Outer Space 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 #424B66 Secondary #AEB4B8 Surface #F1F2F0 Support #7D92A7 Anchor #2E3236

Outer Space 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 #424B66 Surface #14161A Highlight #F4F6F8 Secondary #5B6672 Accent #646D87

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

Vintage Leather Lead · 5 colors

Lead #424B66 Secondary #7F4535 Surface #EED7C2 Accent #365246 Anchor #582239

Outer Space 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 #F8F4EF Accent #424B66 Secondary #6F737D Support #9D8F88 Ink #18140F

Outer Space 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 Outer Space carrying the quiet middle.

Build a working theme in the generator →

Color Lab

How #424B66 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 39/100

Neutral

Balanced temperature — flexible, sits between warm and cool schemes.

Softness 41/100

Moderate

Middle-weight — neither delicate nor heavy.

Depth 56/100

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 40/100

Low

A faint retro warmth without tipping into sepia.

Luxury 60/100

Moderate

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

Brand distinctiveness 18/100

Very low

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

UI accent fit 56/100

Moderate

Workable accent with care around contrast.

Surface fit 44/100

Moderate

Usable as a tinted surface in measured doses.

Print safety 92/100

Very high

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #424B66

For UI

For branding

For interior

For fashion

People also use #424B66 with

Teal Blue Eggplant Ebony Gainsboro Charcoal

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 8.6:1. Use

Subtle surface Use #D8DAE2 for cards and hover fills. Tint 80

Avoid beside #454266 — 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 #424B66 at work across the surfaces designers actually ship.

Website / UI

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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: #424B66;
  --color-base-rgb: 66 75 102;
  --color-base-oklch: oklch(41.6% 0.047 270.0);
  --color-50: #F6F6F9;
  --color-100: #E6E8EF;
  --color-200: #CED2DF;
  --color-300: #AAB1C5;
  --color-400: #8890AA;
  --color-500: #68718D;
  --color-600: #545A6E;
  --color-700: #3F4350;
  --color-800: #2B2E35;
  --color-900: #1C1D21;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  outer-space: {
    50: '#F6F6F9',
    100: '#E6E8EF',
    200: '#CED2DF',
    300: '#AAB1C5',
    400: '#8890AA',
    500: '#68718D',
    600: '#545A6E',
    700: '#3F4350',
    800: '#2B2E35',
    900: '#1C1D21',
  },
}

$base: #424B66;
$base-ink: #FFFFFF;
$base-50: #F6F6F9;
$base-100: #E6E8EF;
$base-200: #CED2DF;
$base-300: #AAB1C5;
$base-400: #8890AA;
$base-500: #68718D;
$base-600: #545A6E;
$base-700: #3F4350;
$base-800: #2B2E35;
$base-900: #1C1D21;
$base-hover: #353C51;
$base-subtle: #C4C8D4;

{
    "color": {
        "base": {
            "value": "#424B66",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F6F6F9",
                "type": "color"
            },
            "100": {
                "value": "#E6E8EF",
                "type": "color"
            },
            "200": {
                "value": "#CED2DF",
                "type": "color"
            },
            "300": {
                "value": "#AAB1C5",
                "type": "color"
            },
            "400": {
                "value": "#8890AA",
                "type": "color"
            },
            "500": {
                "value": "#68718D",
                "type": "color"
            },
            "600": {
                "value": "#545A6E",
                "type": "color"
            },
            "700": {
                "value": "#3F4350",
                "type": "color"
            },
            "800": {
                "value": "#2B2E35",
                "type": "color"
            },
            "900": {
                "value": "#1C1D21",
                "type": "color"
            }
        }
    }
}

Palettes built on #424B66

Color Lab

Pairs with #424B66

UI roles & guardrails

In real applications

Scales

Every model

Export