#40adef

At a glance

Every number on this page in one read: what #40adef is made of, how bright it looks, and which way it leans.

Design tokens

The same ramp in the four formats a team actually needs. Paste one and the whole palette lands with it.

:root {
  --brand-50: #F2F9FC;
  --brand-100: #E6F2FA;
  --brand-200: #C5E4F7;
  --brand-300: #97D3F6;
  --brand-400: #64BCF2;
  --brand-500: #40adef;
  --brand-600: #1394E2;
  --brand-700: #107BBC;
  --brand-800: #0D6397;
  --brand-900: #0E496D;
  --brand-950: #092E44;
  --brand: #40adef;
  --brand-ink: #000000;
  --brand-surface: #F4F8FA;
  --brand-border: #C0DCED;
  --brand-hover: #1F9FEC;
  --brand-pressed: #128CD6;
}
@media (prefers-color-scheme: dark) {
  :root {
    --brand-surface: #141E24;
    --brand-ink: #D3E4EE;
  }
}

theme: {
  extend: {
    colors: {
      brand: {
        50: '#F2F9FC',
        100: '#E6F2FA',
        200: '#C5E4F7',
        300: '#97D3F6',
        400: '#64BCF2',
        500: '#40adef',
        600: '#1394E2',
        700: '#107BBC',
        800: '#0D6397',
        900: '#0E496D',
        950: '#092E44',
        DEFAULT: '#40adef',
      },
    },
  },
}

$brand: (
  '50': #F2F9FC,
  '100': #E6F2FA,
  '200': #C5E4F7,
  '300': #97D3F6,
  '400': #64BCF2,
  '500': #40adef,
  '600': #1394E2,
  '700': #107BBC,
  '800': #0D6397,
  '900': #0E496D,
  '950': #092E44,
);
$brand-base: #40adef;
$brand-ink: #000000;

@function brand($step) { @return map-get($brand, $step); }

{
  "color": {
    "brand": {
      "50": { "$value": "#F2F9FC", "$type": "color" },
      "100": { "$value": "#E6F2FA", "$type": "color" },
      "200": { "$value": "#C5E4F7", "$type": "color" },
      "300": { "$value": "#97D3F6", "$type": "color" },
      "400": { "$value": "#64BCF2", "$type": "color" },
      "500": { "$value": "#40adef", "$type": "color" },
      "600": { "$value": "#1394E2", "$type": "color" },
      "700": { "$value": "#107BBC", "$type": "color" },
      "800": { "$value": "#0D6397", "$type": "color" },
      "900": { "$value": "#0E496D", "$type": "color" },
      "950": { "$value": "#092E44", "$type": "color" }
    },
    "brandInk": { "$value": "#000000", "$type": "color" }
  }
}

Best text color

Only one of black and white can be right. This is the one, with the number that proves it.

Make it accessible

A contrast checker tells you that you failed. This tells you what to ship instead — same hue, same saturation, lightness moved only as far as WCAG demands.

Accessibility — WCAG contrast

Contrast is symmetric, so each row covers both directions: #40adef as text on that neutral, and that neutral as text on #40adef.

Roughly one man in twelve has some form of colour vision deficiency. If any of the three panels above is hard to tell apart from a neighbouring colour in your palette, add a shape, an icon or a label so the meaning does not rest on hue alone.

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #40adef is pinned to step 500; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

:root {
  --brand-50: oklch(0.97 0.034 239.7);
  --brand-100: oklch(0.94 0.055 239.7);
  --brand-200: oklch(0.88 0.082 239.7);
  --brand-300: oklch(0.80 0.107 239.7);
  --brand-400: oklch(0.72 0.126 239.7);
  --brand-500: oklch(0.64 0.137 239.7);
  --brand-600: oklch(0.56 0.137 239.7);
  --brand-700: oklch(0.48 0.129 239.7);
  --brand-800: oklch(0.40 0.115 239.7);
  --brand-900: oklch(0.32 0.096 239.7);
  --brand-950: oklch(0.24 0.075 239.7);
}

Colors that work with #40adef

Not a palette — a role sheet. Each swatch answers one question you will hit while building the component.

In real components

The same eight roles, wired into the interface patterns you will actually build with them. Every state below is a computed value, not a mock-up.

How to use #40adef

Derived from its contrast, chroma and lightness — not from taste.

Meaning and mood

What a colour in this family tends to signal, and how this particular chroma and lightness change the reading.

Similar colors

One move away from this hex in each direction. Every swatch is its own page.

Color relationships

The wheel positions with their names attached, so you can grab the one you actually need.

Transparency

What each alpha value actually composites to. The top row is #40adef over white; the bottom row is the same alpha over a checkerboard, so you can see what survives on a photo or a video.

rgba(64, 173, 239, 0.5)
rgb(64 173 239 / 50%)
#40adef80
hsl(203 85% 59% / 50%)
color-mix(in srgb, #40adef 50%, transparent)

Gradients from #40adef

Six recipes, each built from this hex and shown with the exact CSS that produced it.

background: linear-gradient(135deg, #78C5F4, #40adef 45%, #0A4D76);

background: linear-gradient(120deg, #40adef, #3D24ED);

background: linear-gradient(90deg, #40adef, #EF8240);

background: radial-gradient(120% 120% at 20% 0%, #95D1F6 0%, #40adef 45%, #0A4D76 100%);

background: linear-gradient(180deg, #F4F8FA, #ffffff);

background: radial-gradient(60% 60% at 15% 20%, #6FF3D8 0%, transparent 60%), radial-gradient(55% 55% at 85% 15%, #5C62F1 0%, transparent 60%), radial-gradient(70% 70% at 50% 95%, #0A4D76 0%, transparent 65%), #40adef;

Nearest named colors

Ranked with CIEDE2000 across all 139 CSS keywords. Under ΔE 2 the eye stops telling them apart; over ΔE 10 they are plainly different colors.

#40adef in the real world

Where a color in this family tends to land, and the interface roles it is usually asked to play.

Explore nearby colors

Small, deliberate steps away from this hex — useful when you are hunting for the version of a colour that finally feels right.