#657F9A is a muted, cool indigo. On the Color Lab it reads clean and engineered, restrained and easy to live with. It carries a legible label as a UI accent and reproduces cleanly in print.
Not just a swatch — here's how #657F9A works with other colors. Named schemes with #657F9A in its natural role, and a note on why the supporting colors balance it.
Slate Gray opens this coastal palette with sea-glass and warm sand alongside it, grounded by driftwood grey and a deep-navy anchor.
Slate Gray keeps this Nordic scheme quiet — cool greys and a soft white around it, a muted-blue support and a charcoal anchor.
Slate Gray is the vivid signal in this product UI — on a near-black surface with cool white, a slate grey and a lighter tint of Slate Gray.
Slate Gray plays the worn-leather lead, deepened by saddle brown and an oxblood anchor, softened by aged cream and cooled by a muted forest green.
Slate Gray 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 Slate Gray carrying the quiet middle.
How #657F9A 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 #657F9A at work across the surfaces designers actually ship.
:root {
--color-base: #657F9A;
--color-base-rgb: 101 127 154;
--color-base-oklch: oklch(58.6% 0.051 249.7);
--color-50: #F6F7F9;
--color-100: #E6EAEF;
--color-200: #CED6DF;
--color-300: #AAB7C5;
--color-400: #8898AA;
--color-500: #687A8D;
--color-600: #54606E;
--color-700: #3F4750;
--color-800: #2B3035;
--color-900: #1C1F21;
--color-on-base: #141310;
}
// tailwind.config.js
colors: {
slate-gray: {
50: '#F6F7F9',
100: '#E6EAEF',
200: '#CED6DF',
300: '#AAB7C5',
400: '#8898AA',
500: '#687A8D',
600: '#54606E',
700: '#3F4750',
800: '#2B3035',
900: '#1C1F21',
},
}
$base: #657F9A; $base-ink: #141310; $base-50: #F6F7F9; $base-100: #E6EAEF; $base-200: #CED6DF; $base-300: #AAB7C5; $base-400: #8898AA; $base-500: #687A8D; $base-600: #54606E; $base-700: #3F4750; $base-800: #2B3035; $base-900: #1C1F21; $base-hover: #51657B; $base-subtle: #D3D9DF;
{
"color": {
"base": {
"value": "#657F9A",
"type": "color"
},
"onBase": {
"value": "#141310",
"type": "color"
},
"scale": {
"50": {
"value": "#F6F7F9",
"type": "color"
},
"100": {
"value": "#E6EAEF",
"type": "color"
},
"200": {
"value": "#CED6DF",
"type": "color"
},
"300": {
"value": "#AAB7C5",
"type": "color"
},
"400": {
"value": "#8898AA",
"type": "color"
},
"500": {
"value": "#687A8D",
"type": "color"
},
"600": {
"value": "#54606E",
"type": "color"
},
"700": {
"value": "#3F4750",
"type": "color"
},
"800": {
"value": "#2B3035",
"type": "color"
},
"900": {
"value": "#1C1F21",
"type": "color"
}
}
}
}