What color is #42018B?

#42018B is a dark, vivid violet. In RGB it is rgb(66, 1, 139), and in HSL hsl(268, 99%, 27%).

Is #42018B accessible as text?

On white, #42018B has a contrast ratio of 13.05:1 (passes WCAG AA for body text); on black it is 1.61:1 (fails). For text placed on #42018B, use white for the best readability.

What is the closest Tailwind color to #42018B?

The nearest Tailwind CSS token is violet-900 (#4D179A).

What colors go well with #42018B?

#42018B pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #498901. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #42018B below.

Is #42018B good for buttons?

#42018B works well for buttons and highlights, but use white text on #42018B — black text only reaches 1.61:1, below the 4.5:1 needed for normal-size labels.

Is #42018B the same as CSS indigo?

No — #42018B is not the CSS named color indigo, but indigo (#4B0082) is the closest CSS named color.

#42018B Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #42018B

Not just a swatch — here's how #42018B works with other colors. Named schemes with #42018B in its natural role, and a note on why the supporting colors balance it.

Luxury Packaging Feature · 5 colors

Feature #42018B Anchor #141210 Accent #DA9856 Secondary #292732 Surface #F3ECE3

Indigo carries the depth in this luxury scheme, offset by a brass accent and near-black and held together by a deep neutral and an off-white surface.

Moody Editorial Color · 5 colors

Color #42018B Anchor #2A2A2E Secondary #6E6E74 Surface #EEE5DA Accent #2D0044

Indigo adds the colour to this moody editorial scheme — charcoal and a mid-grey around it, a bone highlight, and a muted jewel accent drawn from Indigo.

Berry & Cream Lead · 5 colors

Lead #42018B Surface #F5E5D7 Anchor #5C2141 Accent #E5C2C8 Secondary #332B2F

Indigo 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 #42018B Secondary #5E567E Support #9D9088 Ink #18140F

Indigo 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 Indigo carrying the quiet middle.

Coastal Morning Lead · 5 colors

Lead #42018B Accent #A5C4C3 Surface #E9D6BF Secondary #9AA0A1 Anchor #23334A

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

Build a working theme in the generator →

Color Lab

How #42018B 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 28/100

Cool

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

Softness 23/100

Low

Firm and assertive — carries weight and contrast.

Depth 70/100

High

Deep and grounding — anchors a layout, strong dark-mode base.

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 65/100

High

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

Brand distinctiveness 72/100

High

Bold and ownable — memorable as a primary brand color.

UI accent fit 48/100

Moderate

Workable accent with care around contrast.

Surface fit 18/100

Very low

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

Print safety 75/100

High

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #42018B

For UI

For branding

For interior

For fashion

People also use #42018B with

Zaffre Mardi Gras Fern Green Gainsboro Onyx

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 13.1:1. Use

Subtle surface Use #D8BFF4 for cards and hover fills. Tint 80

Avoid beside #6E0189 — 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 #42018B 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: #42018B;
  --color-base-rgb: 66 1 139;
  --color-base-oklch: oklch(33.7% 0.186 293.4);
  --color-50: #F7F0FE;
  --color-100: #E9D8FD;
  --color-200: #D4B1FC;
  --color-300: #B378F7;
  --color-400: #9447EB;
  --color-500: #7523D2;
  --color-600: #5D239F;
  --color-700: #451F6F;
  --color-800: #2F1948;
  --color-900: #1E112C;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  indigo: {
    50: '#F7F0FE',
    100: '#E9D8FD',
    200: '#D4B1FC',
    300: '#B378F7',
    400: '#9447EB',
    500: '#7523D2',
    600: '#5D239F',
    700: '#451F6F',
    800: '#2F1948',
    900: '#1E112C',
  },
}

$base: #42018B;
$base-ink: #FFFFFF;
$base-50: #F7F0FE;
$base-100: #E9D8FD;
$base-200: #D4B1FC;
$base-300: #B378F7;
$base-400: #9447EB;
$base-500: #7523D2;
$base-600: #5D239F;
$base-700: #451F6F;
$base-800: #2F1948;
$base-900: #1E112C;
$base-hover: #33016E;
$base-subtle: #C49DF1;

{
    "color": {
        "base": {
            "value": "#42018B",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F7F0FE",
                "type": "color"
            },
            "100": {
                "value": "#E9D8FD",
                "type": "color"
            },
            "200": {
                "value": "#D4B1FC",
                "type": "color"
            },
            "300": {
                "value": "#B378F7",
                "type": "color"
            },
            "400": {
                "value": "#9447EB",
                "type": "color"
            },
            "500": {
                "value": "#7523D2",
                "type": "color"
            },
            "600": {
                "value": "#5D239F",
                "type": "color"
            },
            "700": {
                "value": "#451F6F",
                "type": "color"
            },
            "800": {
                "value": "#2F1948",
                "type": "color"
            },
            "900": {
                "value": "#1E112C",
                "type": "color"
            }
        }
    }
}

Palettes built on #42018B

Color Lab

Pairs with #42018B

UI roles & guardrails

In real applications

Scales

Every model

Export