Free Color Palette Generator API — Harmonies, Gradients & WCAG Contrast Check

#api #design #css #webdev

Building a Design System? Start with Colors.

Picking colors that work together is harder than it looks. You need harmonious palettes, accessible contrast ratios, and gradient stops — all programmatically.

Color Palette Generator API

A free REST API that generates color schemes based on color theory, checks WCAG accessibility, and creates gradient stops.

Generate a Palette

curl "https://color-palette-generator-api.p.rapidapi.com/palette?color=%23FF6B35&type=complementary" \
  -H "X-RapidAPI-Key: YOUR_KEY"

Response:

{
  "base": "#FF6B35",
  "type": "complementary",
  "palette": ["#FF6B35", "#3594FF"],
  "hex": ["#FF6B35", "#3594FF"],
  "rgb": ["rgb(255,107,53)", "rgb(53,148,255)"],
  "hsl": ["hsl(16,100%,60%)", "hsl(212,100%,60%)"]
}

Harmony Types

Type	Colors	Description
`complementary`	2	Opposite on color wheel
`triadic`	3	120° apart
`analogous`	3	Adjacent colors
`split-complementary`	3	Base + 2 near-complement
`tetradic`	4	Rectangle on wheel
`monochromatic`	5	Same hue, varied lightness

WCAG Contrast Check

curl "https://color-palette-generator-api.p.rapidapi.com/contrast?foreground=%23FFFFFF&background=%23FF6B35"

{
  "ratio": 3.12,
  "AA_normal": false,
  "AA_large": true,
  "AAA_normal": false,
  "AAA_large": false
}

Use Cases

Design systems: Auto-generate accessible color tokens
Theming: Create dark/light mode palettes from a single brand color
Data visualization: Generate distinct, harmonious chart colors
CSS gradients: Get stop points for smooth transitions

Free Tier

100 requests/month. No credit card.

Try it free: Color Palette API on RapidAPI

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