Korea Payroll & Tax API › korean-age

Korean age calculation

Korean age calculation: international age (the legal standard in South Korea since June 2023), year age, traditional counting age, zodiac animal, and the next birthday.

Price: $0.01 USDC per call over REST (x402 on Base, no API key). MCP: free as korean_age at https://api.kkuldogu.com/mcp. Basis year: 2026.

Input

Field	Type	Required	Description
`birthDate`	string	yes	Date of birth (YYYY-MM-DD)
`referenceDate`	string		Date to evaluate; default today (YYYY-MM-DD)

Example request

curl -X POST https://api.kkuldogu.com/v1/korean-age -H "content-type: application/json" \
  -d '{"birthDate":"1995-03-15","referenceDate":"2026-11-12"}'

Without payment this returns 402 with x402 payment requirements; an x402 client pays $0.01 USDC and retries.

Example response

{
  "basisYear": 2026,
  "currency": "KRW",
  "disclaimer": "For reference only, not legal or tax advice. Uses official 2026 Korean rates and the same formulas as the kkuldogu.com calculators; actual payroll, NHIS/NPS notices and tax settlement can differ.",
  "source": "https://kkuldogu.com",
  "tool": "korean-age",
  "input": {
    "birthDate": "1995-03-15",
    "referenceDate": "2026-11-12"
  },
  "result": {
    "internationalAge": 31,
    "yearAge": 31,
    "traditionalKoreanAge": 32,
    "zodiac": "pig",
    "isBirthday": false,
    "nextBirthday": "2027-03-15",
    "daysUntilNextBirthday": 123,
    "dayOfLife": 11566
  }
}

For reference only, not legal or tax advice. Uses official 2026 Korean rates and the same formulas as the kkuldogu.com calculators; actual payroll, NHIS/NPS notices and tax settlement can differ. · Calculators for people (Korean): kkuldogu.com · API home · llms.txt · OpenAPI