Color Contrast

Developer REST API MCP

Compute the WCAG 2.1 contrast ratio between two colours (accepts #rgb, #rrggbb, and rgb()/rgba() formats) and report whether it passes AA/AAA for normal and large text.

This page documents the HTTP endpoint POST /api/tools/color-contrast/execute. See the MCP reference →

Use in the browser View as Markdown

Call it over REST

POST https://api.findutils.com/api/tools/color-contrast/execute · no API keys · 60 requests/min per IP

Execute — verified arguments

curl -X POST https://api.findutils.com/api/tools/color-contrast/execute \
  -H "Content-Type: application/json" \
  -d '{
    "foreground": "#000",
    "background": "#fff"
  }'

Parameter schema for this endpoint

curl https://api.findutils.com/api/tools/color-contrast

Interactive docs · OpenAPI 3.1 spec · All REST tools

Input schema

Argument	Type	Required	Description
foreground	string	yes	Foreground / text colour.
background	string	yes	Background colour.

Example arguments (verified)

{
  "foreground": "#000",
  "background": "#fff"
}

Also an MCP tool

Claude, Cursor, and any MCP client can call this tool as findutils:color_contrast after one connect command.

Connect once

claude mcp add findutils --transport http https://mcp.findutils.com/

Open the MCP reference for Color Contrast →

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