#4281BB is a mid-toned, cool indigo. On the Color Lab it reads clean and engineered. It carries a legible label as a UI accent and sits well as a supporting tone.
Not just a swatch — here's how #4281BB works with other colors. Named schemes with #4281BB in its natural role, and a note on why the supporting colors balance it.
Steel Blue opens this coastal palette with sea-glass and warm sand alongside it, grounded by driftwood grey and a deep-navy anchor.
Steel 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 Steel Blue.
Steel Blue plays the worn-leather lead, deepened by saddle brown and an oxblood anchor, softened by aged cream and cooled by a muted forest green.
Steel Blue sits between cream and a deep berry here, softened by a blush accent and grounded by charcoal.
Steel 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 Steel Blue carrying the quiet middle.
How #4281BB 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 #4281BB at work across the surfaces designers actually ship.
:root {
--color-base: #4281BB;
--color-base-rgb: 66 129 187;
--color-base-oklch: oklch(58.8% 0.111 248.5);
--color-50: #F3F7FB;
--color-100: #E0EBF5;
--color-200: #C3D7EA;
--color-300: #99B9D7;
--color-400: #719AC1;
--color-500: #507CA5;
--color-600: #43627F;
--color-700: #34485B;
--color-800: #25313C;
--color-900: #181F25;
--color-on-base: #141310;
}
// tailwind.config.js
colors: {
steel-blue: {
50: '#F3F7FB',
100: '#E0EBF5',
200: '#C3D7EA',
300: '#99B9D7',
400: '#719AC1',
500: '#507CA5',
600: '#43627F',
700: '#34485B',
800: '#25313C',
900: '#181F25',
},
}
$base: #4281BB; $base-ink: #141310; $base-50: #F3F7FB; $base-100: #E0EBF5; $base-200: #C3D7EA; $base-300: #99B9D7; $base-400: #719AC1; $base-500: #507CA5; $base-600: #43627F; $base-700: #34485B; $base-800: #25313C; $base-900: #181F25; $base-hover: #356897; $base-subtle: #CBD9E7;
{
"color": {
"base": {
"value": "#4281BB",
"type": "color"
},
"onBase": {
"value": "#141310",
"type": "color"
},
"scale": {
"50": {
"value": "#F3F7FB",
"type": "color"
},
"100": {
"value": "#E0EBF5",
"type": "color"
},
"200": {
"value": "#C3D7EA",
"type": "color"
},
"300": {
"value": "#99B9D7",
"type": "color"
},
"400": {
"value": "#719AC1",
"type": "color"
},
"500": {
"value": "#507CA5",
"type": "color"
},
"600": {
"value": "#43627F",
"type": "color"
},
"700": {
"value": "#34485B",
"type": "color"
},
"800": {
"value": "#25313C",
"type": "color"
},
"900": {
"value": "#181F25",
"type": "color"
}
}
}
}