ToolAssay

Parse any CSS color (hex, rgb(), hsl()) and emit all three formats plus relative

Parse any CSS color (hex, rgb(), hsl()) and emit all three formats plus relative luminance. Compute WCAG contrast ratios against a background with AA/AAA pass-fail for normal and large text, and lighten, darken, or mix colors. Built for agents generating accessible UI themes. POST a JSON body like: {"color":"#3498db","background":"#ffffff"}

Answeringour last check, 2026-09-24
1 of 1checks answered this week
44 msmedian answer time
$0.001listed price per call
$0.001price it asked us

Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.

Endpoint

POST https://keyronne.com/api/color

CategoryEverything else
Provider hostkeyronne.com
Networkseip155:8453
Payment schemesexact
Self-reported calls, 30 days5 from 4 payers (the provider's figure, not ours)

Our checks, last 30 days

DayResultHTTPAskedTime
2026-09-24 valid payment request 402$0.001 44 ms

Example input (from the provider)

{
  "body": {
    "background": "#ffffff",
    "color": "#3498db"
  },
  "bodyType": "json",
  "method": "POST",
  "type": "http"
}

Promised output schema (from the provider)

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "properties": {
    "input": {
      "properties": {
        "body": {
          "properties": {
            "background": {
              "description": "Optional second color for a WCAG contrast check.",
              "type": "string"
            },
            "color": {
              "description": "A color: \"#3498db\", \"rgb(52,152,219)\", or \"hsl(204,70%,53%)\".",
              "type": "string"
            },
            "darken": {
              "description": "Decrease lightness by this many percent (0-100).",
              "type": "number"
            },
            "lighten": {
              "description": "Increase lightness by this many percent (0-100).",
              "type": "number"
            },
            "mix": {
              "description": "Blend the color toward this one.",
              "type": "string"
            },
            "weight": {
              "default": 0.5,
              "description": "Mix weight toward \"mix\".",
              "maximum": 1,
              "minimum": 0,
              "type": "number"
            }
          },
          "required": [
            "color"
          ],
          "type": "object"
        },
        "bodyType": {
          "enum": [
            "json"
          ],
          "type": "string"
        },
        "method": {
          "enum": [
            "POST"
          ],
          "type": "string"
        },
        "type": {
          "const": "http",
          "type": "string"
        }
      },
      "type": "object"
    },
    "output": {
      "properties": {
        "adjusted": {
          "description": "Present when lighten/darken is given.",
          "type": "string"
        },
        "contrast": {
          "description": "Present when \"background\" is given.",
          "type": "object"
        },
        "hex": {
          "type": "string"
        },
        "hsl": {
          "type": "object"
        },
        "luminance": {
          "type": "number"
        },
        "mixed": {
          "description": "Present when \"mix\" is given.",
          "type": "string"
        },
        "rgb": {
          "type": "object"
        }
      },
      "type": "object"
    }
  },
  "required": [
    "input"
  ],
  "type": "object"
}

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