#337FC6 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 #337FC6 works with other colors. Named schemes with #337FC6 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 #337FC6 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 #337FC6 at work across the surfaces designers actually ship.
:root {
--color-base: #337FC6;
--color-base-rgb: 51 127 198;
--color-base-oklch: oklch(58.4% 0.132 249.9);
--color-50: #F2F8FC;
--color-100: #DEEBF7;
--color-200: #BED7EE;
--color-300: #92B9DE;
--color-400: #689BCA;
--color-500: #467CAE;
--color-600: #3C6286;
--color-700: #30485F;
--color-800: #22313F;
--color-900: #171F27;
--color-on-base: #141310;
}
// tailwind.config.js
colors: {
steel-blue: {
50: '#F2F8FC',
100: '#DEEBF7',
200: '#BED7EE',
300: '#92B9DE',
400: '#689BCA',
500: '#467CAE',
600: '#3C6286',
700: '#30485F',
800: '#22313F',
900: '#171F27',
},
}
$base: #337FC6; $base-ink: #141310; $base-50: #F2F8FC; $base-100: #DEEBF7; $base-200: #BED7EE; $base-300: #92B9DE; $base-400: #689BCA; $base-500: #467CAE; $base-600: #3C6286; $base-700: #30485F; $base-800: #22313F; $base-900: #171F27; $base-hover: #29669F; $base-subtle: #C6D9E9;
{
"color": {
"base": {
"value": "#337FC6",
"type": "color"
},
"onBase": {
"value": "#141310",
"type": "color"
},
"scale": {
"50": {
"value": "#F2F8FC",
"type": "color"
},
"100": {
"value": "#DEEBF7",
"type": "color"
},
"200": {
"value": "#BED7EE",
"type": "color"
},
"300": {
"value": "#92B9DE",
"type": "color"
},
"400": {
"value": "#689BCA",
"type": "color"
},
"500": {
"value": "#467CAE",
"type": "color"
},
"600": {
"value": "#3C6286",
"type": "color"
},
"700": {
"value": "#30485F",
"type": "color"
},
"800": {
"value": "#22313F",
"type": "color"
},
"900": {
"value": "#171F27",
"type": "color"
}
}
}
}