What color is #403CB4?

#403CB4 is a medium blue-violet. In RGB it is rgb(64, 60, 180), and in HSL hsl(242, 50%, 47%).

Is #403CB4 accessible as text?

On white, #403CB4 has a contrast ratio of 8.32:1 (passes WCAG AA for body text); on black it is 2.52:1 (fails). For text placed on #403CB4, use white for the best readability.

What is the closest Tailwind color to #403CB4?

The nearest Tailwind CSS token is indigo-800 (#372AAC).

What colors go well with #403CB4?

#403CB4 pairs cleanly with neutrals — cream, taupe, charcoal and cool grays — and with its complementary #B0B43C. In UI, a softer accent is often easier to use than the exact complement. Explore the harmonies, shades, tints and ready-made palettes for #403CB4 below.

Is #403CB4 good for buttons?

#403CB4 works well for buttons and highlights, but use white text on #403CB4 — black text only reaches 2.52:1, below the 4.5:1 needed for normal-size labels.

Is #403CB4 the same as CSS darkslateblue?

No — #403CB4 is not the CSS named color darkslateblue, but darkslateblue (#483D8B) is the closest CSS named color.

#403CB4 Color — HEX, RGB, HSL, Palette & Shades

Palettes built on #403CB4

Not just a swatch — here's how #403CB4 works with other colors. Named schemes with #403CB4 in its natural role, and a note on why the supporting colors balance it.

Coastal Morning Lead · 5 colors

Lead #403CB4 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.

Vintage Leather Lead · 5 colors

Lead #403CB4 Secondary #7F4534 Surface #EED7C2 Accent #365247 Anchor #582239

Cerulean plays the worn-leather lead, deepened by saddle brown and an oxblood anchor, softened by aged cream and cooled by a muted forest green.

Modern Café Dominant · 5 colors

Dominant #403CB4 Anchor #3B2923 Surface #F3E1D2 Accent #769F7B Secondary #3C3734

Cerulean anchors this café scheme as the warm mid-tone, lifted by latte cream and a muted sage accent and grounded by espresso brown and a warm charcoal.

Berry & Cream Lead · 5 colors

Lead #403CB4 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 #403CB4 Secondary #7077A1 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.

Build a working theme in the generator →

Color Lab

How #403CB4 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 30/100

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 27/100

Low

A faint retro warmth without tipping into sepia.

Luxury 57/100

Moderate

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

Brand distinctiveness 50/100

Moderate

Recognisable but shares space with nearby hues.

UI accent fit 81/100

Very 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 71/100

High

Reproduces faithfully in CMYK — safe for packaging and print.

Pairs with #403CB4

For UI

For branding

For interior

For fashion

People also use #403CB4 with

Ocean Blue Royal Purple Brass 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 8.3:1. Use

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

Avoid beside #683CB4 — 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 #403CB4 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: #403CB4;
  --color-base-rgb: 64 60 180;
  --color-base-oklch: oklch(44.0% 0.183 277.2);
  --color-50: #F3F3FC;
  --color-100: #E1E0F5;
  --color-200: #C3C2EB;
  --color-300: #9997D8;
  --color-400: #7270C2;
  --color-500: #514EA6;
  --color-600: #444280;
  --color-700: #35335C;
  --color-800: #25243C;
  --color-900: #181825;
  --color-on-base: #FFFFFF;
}

// tailwind.config.js
colors: {
  cerulean: {
    50: '#F3F3FC',
    100: '#E1E0F5',
    200: '#C3C2EB',
    300: '#9997D8',
    400: '#7270C2',
    500: '#514EA6',
    600: '#444280',
    700: '#35335C',
    800: '#25243C',
    900: '#181825',
  },
}

$base: #403CB4;
$base-ink: #FFFFFF;
$base-50: #F3F3FC;
$base-100: #E1E0F5;
$base-200: #C3C2EB;
$base-300: #9997D8;
$base-400: #7270C2;
$base-500: #514EA6;
$base-600: #444280;
$base-700: #35335C;
$base-800: #25243C;
$base-900: #181825;
$base-hover: #333090;
$base-subtle: #C8C7E6;

{
    "color": {
        "base": {
            "value": "#403CB4",
            "type": "color"
        },
        "onBase": {
            "value": "#FFFFFF",
            "type": "color"
        },
        "scale": {
            "50": {
                "value": "#F3F3FC",
                "type": "color"
            },
            "100": {
                "value": "#E1E0F5",
                "type": "color"
            },
            "200": {
                "value": "#C3C2EB",
                "type": "color"
            },
            "300": {
                "value": "#9997D8",
                "type": "color"
            },
            "400": {
                "value": "#7270C2",
                "type": "color"
            },
            "500": {
                "value": "#514EA6",
                "type": "color"
            },
            "600": {
                "value": "#444280",
                "type": "color"
            },
            "700": {
                "value": "#35335C",
                "type": "color"
            },
            "800": {
                "value": "#25243C",
                "type": "color"
            },
            "900": {
                "value": "#181825",
                "type": "color"
            }
        }
    }
}

Palettes built on #403CB4

Color Lab

Pairs with #403CB4

UI roles & guardrails

In real applications

Scales

Every model

Export