#313CB4 is a mid-toned, cool violet. On the Color Lab it reads clean and engineered, quietly premium. It carries a legible label as a UI accent and sits well as a supporting tone.
Not just a swatch — here's how #313CB4 works with other colors. Named schemes with #313CB4 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 #313CB4 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 #313CB4 at work across the surfaces designers actually ship.
:root {
--color-base: #313CB4;
--color-base-rgb: 49 60 180;
--color-base-oklch: oklch(43.1% 0.187 271.7);
--color-50: #F3F3FC;
--color-100: #DEE0F7;
--color-200: #BFC3ED;
--color-300: #9399DC;
--color-400: #6A72C8;
--color-500: #4851AD;
--color-600: #3D4384;
--color-700: #30345E;
--color-800: #23253E;
--color-900: #171826;
--color-on-base: #FFFFFF;
}
// tailwind.config.js
colors: {
cobalt-blue: {
50: '#F3F3FC',
100: '#DEE0F7',
200: '#BFC3ED',
300: '#9399DC',
400: '#6A72C8',
500: '#4851AD',
600: '#3D4384',
700: '#30345E',
800: '#23253E',
900: '#171826',
},
}
$base: #313CB4; $base-ink: #FFFFFF; $base-50: #F3F3FC; $base-100: #DEE0F7; $base-200: #BFC3ED; $base-300: #9399DC; $base-400: #6A72C8; $base-500: #4851AD; $base-600: #3D4384; $base-700: #30345E; $base-800: #23253E; $base-900: #171826; $base-hover: #273090; $base-subtle: #C3C6E7;
{
"color": {
"base": {
"value": "#313CB4",
"type": "color"
},
"onBase": {
"value": "#FFFFFF",
"type": "color"
},
"scale": {
"50": {
"value": "#F3F3FC",
"type": "color"
},
"100": {
"value": "#DEE0F7",
"type": "color"
},
"200": {
"value": "#BFC3ED",
"type": "color"
},
"300": {
"value": "#9399DC",
"type": "color"
},
"400": {
"value": "#6A72C8",
"type": "color"
},
"500": {
"value": "#4851AD",
"type": "color"
},
"600": {
"value": "#3D4384",
"type": "color"
},
"700": {
"value": "#30345E",
"type": "color"
},
"800": {
"value": "#23253E",
"type": "color"
},
"900": {
"value": "#171826",
"type": "color"
}
}
}
}