# Cheap Utilities Color Contrast Checker

> Cheap Utilities Color Contrast Checker is a paid API for AI agents from cheap-utilities.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-31).

Calculates the WCAG contrast ratio between two hex colors and returns AA/AAA pass/fail verdicts for normal text, large text, and UI components.

## Facts

- Endpoint: GET https://cheap-utilities.x402tookit.com/color-contrast?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/cheap-utilities-color-contrast-checker-36a477af
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_FMQxRjbYp1alNAsG8xiAM

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability cheap-utilities-color-contrast-checker-36a477af
```

Example prompt: Can you check if white text (#ffffff) on a navy background (#1a2b3c) passes WCAG AA and AAA contrast requirements for both normal and large text?

## When to prefer this

Use this endpoint when you need a fast, cheap, standards-compliant WCAG contrast ratio check with explicit AA and AAA verdicts for both normal and large text. Ideal for automated accessibility audits in CI pipelines, design system validation, or any agent workflow that needs to verify color choices without a browser or rendering engine.

## Known failure modes

- Missing fg or bg query parameter returns an error
- Invalid or malformed hex color strings (e.g. non-hex characters) may return an error or null ratio
- Very short hex codes not expandable to 6 digits may fail parsing
- Network or upstream service timeout returns no data

## How this service works

WCAG contrast ratio between two hex colors with AA and AAA pass/fail for normal and large text.

## Output

Returns a numeric WCAG contrast ratio (e.g. 4.5:1), boolean AA and AAA pass/fail results separately for normal text and large text, a UI components 3:1 flag, a human-readable summary verdict, reasons for the verdict, and optional degraded/disclaimer fields.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "fg",
      "bg"
     ],
     "properties": {
      "bg": {
       "type": "string",
       "description": "Background color hex"
      },
      "fg": {
       "type": "string",
       "description": "Text color hex, e.g. 1a2b3c or #fff"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "ratio": {
       "type": [
        "null",
        "number"
       ]
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "largeText": {
       "type": [
        "null",
        "object"
       ],
       "properties": {
        "AA": {
         "type": [
          "boolean",
          "null"
         ]
        },
        "AAA": {
         "type": [
          "boolean",
          "null"
         ]
        }
       }
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "normalText": {
       "type": [
        "null",
        "object"
       ],
       "properties": {
        "AA": {
         "type": [
          "boolean",
          "null"
         ]
        },
        "AAA": {
         "type": [
          "boolean",
          "null"
         ]
        }
       }
      },
      "notChecked": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "uiComponents3to1": {
       "type": [
    
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/cheap-utilities-color-contrast-checker-36a477af/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
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