#273FBA 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 #273FBA works with other colors. Named schemes with #273FBA 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 #273FBA 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 #273FBA at work across the surfaces designers actually ship.
:root {
--color-base: #273FBA;
--color-base-rgb: 39 63 186;
--color-base-oklch: oklch(43.7% 0.194 268.1);
--color-50: #F2F4FD;
--color-100: #DDE1F9;
--color-200: #BCC5F1;
--color-300: #8E9CE2;
--color-400: #6375CF;
--color-500: #4154B4;
--color-600: #384689;
--color-700: #2D3662;
--color-800: #212640;
--color-900: #161927;
--color-on-base: #FFFFFF;
}
// tailwind.config.js
colors: {
cobalt-blue: {
50: '#F2F4FD',
100: '#DDE1F9',
200: '#BCC5F1',
300: '#8E9CE2',
400: '#6375CF',
500: '#4154B4',
600: '#384689',
700: '#2D3662',
800: '#212640',
900: '#161927',
},
}
$base: #273FBA; $base-ink: #FFFFFF; $base-50: #F2F4FD; $base-100: #DDE1F9; $base-200: #BCC5F1; $base-300: #8E9CE2; $base-400: #6375CF; $base-500: #4154B4; $base-600: #384689; $base-700: #2D3662; $base-800: #212640; $base-900: #161927; $base-hover: #1F3394; $base-subtle: #BFC6E9;
{
"color": {
"base": {
"value": "#273FBA",
"type": "color"
},
"onBase": {
"value": "#FFFFFF",
"type": "color"
},
"scale": {
"50": {
"value": "#F2F4FD",
"type": "color"
},
"100": {
"value": "#DDE1F9",
"type": "color"
},
"200": {
"value": "#BCC5F1",
"type": "color"
},
"300": {
"value": "#8E9CE2",
"type": "color"
},
"400": {
"value": "#6375CF",
"type": "color"
},
"500": {
"value": "#4154B4",
"type": "color"
},
"600": {
"value": "#384689",
"type": "color"
},
"700": {
"value": "#2D3662",
"type": "color"
},
"800": {
"value": "#212640",
"type": "color"
},
"900": {
"value": "#161927",
"type": "color"
}
}
}
}