#3039BB 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 #3039BB works with other colors. Named schemes with #3039BB in its natural role, and a note on why the supporting colors balance it.
Cobalt Blue is the vivid signal in this product UI — on a near-black surface with cool white, a slate grey and a lighter tint of Cobalt Blue.
Cobalt Blue opens this coastal palette with sea-glass and warm sand alongside it, grounded by driftwood grey and a deep-navy anchor.
Cobalt Blue sits between cream and a deep berry here, softened by a blush accent and grounded by charcoal.
Cobalt Blue 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 Cobalt Blue carrying the quiet middle.
Cobalt Blue glows at the center of this sunset palette, joined by coral and gold, deepened by a plum anchor and cooled with cream.
How #3039BB 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 #3039BB at work across the surfaces designers actually ship.
:root {
--color-base: #3039BB;
--color-base-rgb: 48 57 187;
--color-base-oklch: oklch(43.2% 0.200 271.6);
--color-50: #F2F3FC;
--color-100: #DEE0F7;
--color-200: #BEC1EE;
--color-300: #9297DE;
--color-400: #686FCA;
--color-500: #464DAE;
--color-600: #3C4186;
--color-700: #30335F;
--color-800: #22243F;
--color-900: #171827;
--color-on-base: #FFFFFF;
}
// tailwind.config.js
colors: {
cobalt-blue: {
50: '#F2F3FC',
100: '#DEE0F7',
200: '#BEC1EE',
300: '#9297DE',
400: '#686FCA',
500: '#464DAE',
600: '#3C4186',
700: '#30335F',
800: '#22243F',
900: '#171827',
},
}
$base: #3039BB; $base-ink: #FFFFFF; $base-50: #F2F3FC; $base-100: #DEE0F7; $base-200: #BEC1EE; $base-300: #9297DE; $base-400: #686FCA; $base-500: #464DAE; $base-600: #3C4186; $base-700: #30335F; $base-800: #22243F; $base-900: #171827; $base-hover: #262E95; $base-subtle: #C3C6E8;
{
"color": {
"base": {
"value": "#3039BB",
"type": "color"
},
"onBase": {
"value": "#FFFFFF",
"type": "color"
},
"scale": {
"50": {
"value": "#F2F3FC",
"type": "color"
},
"100": {
"value": "#DEE0F7",
"type": "color"
},
"200": {
"value": "#BEC1EE",
"type": "color"
},
"300": {
"value": "#9297DE",
"type": "color"
},
"400": {
"value": "#686FCA",
"type": "color"
},
"500": {
"value": "#464DAE",
"type": "color"
},
"600": {
"value": "#3C4186",
"type": "color"
},
"700": {
"value": "#30335F",
"type": "color"
},
"800": {
"value": "#22243F",
"type": "color"
},
"900": {
"value": "#171827",
"type": "color"
}
}
}
}