#3947BF is a mid-toned, cool violet. On the Color Lab it reads clean and engineered, bold and ownable. It carries a legible label as a UI accent and sits well as a supporting tone.
Not just a swatch — here's how #3947BF works with other colors. Named schemes with #3947BF in its natural role, and a note on why the supporting colors balance it.
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.
Cerulean opens this coastal palette with sea-glass and warm sand alongside it, grounded by driftwood grey and a deep-navy anchor.
Cerulean sits between cream and a deep berry here, softened by a blush accent and grounded by charcoal.
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.
Cerulean glows at the center of this sunset palette, joined by coral and gold, deepened by a plum anchor and cooled with cream.
How #3947BF 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.
Not a swatch to memorise — a color to build with. Here is #3947BF at work across the surfaces designers actually ship.
:root {
--color-base: #3947BF;
--color-base-rgb: 57 71 191;
--color-base-oklch: oklch(46.4% 0.187 271.8);
--color-50: #F3F4FC;
--color-100: #DFE1F6;
--color-200: #C0C5EC;
--color-300: #959CDA;
--color-400: #6C75C6;
--color-500: #4B54AA;
--color-600: #3F4683;
--color-700: #32365D;
--color-800: #23263D;
--color-900: #171926;
--color-on-base: #FFFFFF;
}
// tailwind.config.js
colors: {
cerulean: {
50: '#F3F4FC',
100: '#DFE1F6',
200: '#C0C5EC',
300: '#959CDA',
400: '#6C75C6',
500: '#4B54AA',
600: '#3F4683',
700: '#32365D',
800: '#23263D',
900: '#171926',
},
}
$base: #3947BF; $base-ink: #FFFFFF; $base-50: #F3F4FC; $base-100: #DFE1F6; $base-200: #C0C5EC; $base-300: #959CDA; $base-400: #6C75C6; $base-500: #4B54AA; $base-600: #3F4683; $base-700: #32365D; $base-800: #23263D; $base-900: #171926; $base-hover: #2E399A; $base-subtle: #C8CBE8;
{
"color": {
"base": {
"value": "#3947BF",
"type": "color"
},
"onBase": {
"value": "#FFFFFF",
"type": "color"
},
"scale": {
"50": {
"value": "#F3F4FC",
"type": "color"
},
"100": {
"value": "#DFE1F6",
"type": "color"
},
"200": {
"value": "#C0C5EC",
"type": "color"
},
"300": {
"value": "#959CDA",
"type": "color"
},
"400": {
"value": "#6C75C6",
"type": "color"
},
"500": {
"value": "#4B54AA",
"type": "color"
},
"600": {
"value": "#3F4683",
"type": "color"
},
"700": {
"value": "#32365D",
"type": "color"
},
"800": {
"value": "#23263D",
"type": "color"
},
"900": {
"value": "#171926",
"type": "color"
}
}
}
}