Color Converter API

Convert color codes between HEX, RGB, HSL, HWB and OKLCH. CSS keyword and Tailwind v3 matching, WCAG contrast ratios. Free, instant, no sign-up.

The Color Converter is also available as a free REST API. Send a POST request with a JSON body to https://dot.tools/api/tools/color-converter — no authentication, no API key, CORS enabled. Successful calls return { "ok": true, "result": { … } }; failures return HTTP 400 or 422 with an error body.

Request body

Field	Type	Required	Description
`color`	string	required	Color in any sRGB notation: #rgb/#rgba/#rrggbb/#rrggbbaa, rgb()/rgba(), hsl()/hsla(), hwb() (comma or space/slash syntax), or a CSS color keyword. OKLCH input is not accepted (out-of-gamut mapping), but OKLCH output is always provided.

Response

Field	Type	Required	Description
`hex`	string	required	Lowercase hex, 8 digits when alpha < 1 (e.g. #8b5cf6 or #8b5cf680).
`rgb`	object	required
`hsl`	object	required
`hwb`	object	required
`oklch`	object	required
`keyword`	unknown	required	CSS keyword when the RGB channels exactly equal a named color, else null.
`tailwind`	unknown	required	Nearest Tailwind v3 palette color, or null when the nearest match is farther than 0.1 OKLab units.
`contrastOnWhite`	number	required	WCAG contrast ratio against pure white, compositing alpha over white first. 2 decimals.
`contrastOnBlack`	number	required	WCAG contrast ratio against pure black, compositing alpha over black first. 2 decimals.

Example request

curl -X POST https://dot.tools/api/tools/color-converter \
  -H 'Content-Type: application/json' \
  -d '{
  "color": "#8b5cf6"
}'

Sample response

{
  "ok": true,
  "result": {
    "hex": "#8b5cf6",
    "rgb": {
      "r": 139,
      "g": 92,
      "b": 246,
      "a": 1
    },
    "hsl": {
      "h": 258.3,
      "s": 89.5,
      "l": 66.3,
      "a": 1
    },
    "hwb": {
      "h": 258.3,
      "w": 36.1,
      "b": 3.5,
      "a": 1
    },
    "oklch": {
      "l": 0.6056,
      "c": 0.2189,
      "h": 292.72,
      "a": 1
    },
    "keyword": null,
    "tailwind": {
      "name": "violet-500",
      "hex": "#8b5cf6",
      "distance": 0
    },
    "contrastOnWhite": 4.23,
    "contrastOnBlack": 4.96
  }
}

Use the free Color Converter in your browser, read the Color Converter guide, or import the full OpenAPI specification.