#307DA9 is a mid-toned, cool blue. 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 #307DA9 works with other colors. Named schemes with #307DA9 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 #307DA9 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 #307DA9 at work across the surfaces designers actually ship.
:root {
--color-base: #307DA9;
--color-base-rgb: 48 125 169;
--color-base-oklch: oklch(56.2% 0.101 237.6);
--color-50: #F3F9FC;
--color-100: #DFEEF7;
--color-200: #BFDCED;
--color-300: #93C1DC;
--color-400: #6BA5C7;
--color-500: #4988AC;
--color-600: #3E6A84;
--color-700: #314D5E;
--color-800: #23343E;
--color-900: #172126;
--color-on-base: #141310;
}
// tailwind.config.js
colors: {
steel-blue: {
50: '#F3F9FC',
100: '#DFEEF7',
200: '#BFDCED',
300: '#93C1DC',
400: '#6BA5C7',
500: '#4988AC',
600: '#3E6A84',
700: '#314D5E',
800: '#23343E',
900: '#172126',
},
}
$base: #307DA9; $base-ink: #141310; $base-50: #F3F9FC; $base-100: #DFEEF7; $base-200: #BFDCED; $base-300: #93C1DC; $base-400: #6BA5C7; $base-500: #4988AC; $base-600: #3E6A84; $base-700: #314D5E; $base-800: #23343E; $base-900: #172126; $base-hover: #276589; $base-subtle: #C1D8E6;
{
"color": {
"base": {
"value": "#307DA9",
"type": "color"
},
"onBase": {
"value": "#141310",
"type": "color"
},
"scale": {
"50": {
"value": "#F3F9FC",
"type": "color"
},
"100": {
"value": "#DFEEF7",
"type": "color"
},
"200": {
"value": "#BFDCED",
"type": "color"
},
"300": {
"value": "#93C1DC",
"type": "color"
},
"400": {
"value": "#6BA5C7",
"type": "color"
},
"500": {
"value": "#4988AC",
"type": "color"
},
"600": {
"value": "#3E6A84",
"type": "color"
},
"700": {
"value": "#314D5E",
"type": "color"
},
"800": {
"value": "#23343E",
"type": "color"
},
"900": {
"value": "#172126",
"type": "color"
}
}
}
}