Korea Payroll & Tax API › payroll-batch

South Korea monthly payroll run for up to 100 employees in one call

South Korea monthly payroll run for up to 100 employees in one call: per-employee take-home pay with each deduction (national pension, health, long-term care, employment insurance, income tax from the 2026 NTS withholding table, local income tax), employer social-insurance contributions, and company-wide totals including total employer cost. Industrial accident insurance (industry-specific rate) is not included.

Price: $0.10 USDC per call over REST (x402 on Base, no API key). MCP: paid-only — the MCP tool returns payment instructions. Basis year: 2026.

Input

Example request

curl -X POST https://api.kkuldogu.com/v1/payroll-batch -H "content-type: application/json" \
  -d '{"employees":[{"id":"kim","annualSalary":40000000},{"id":"lee","monthlySalary":5000000,"dependents":3,"children8to20":1}]}'

Without payment this returns 402 with x402 payment requirements; an x402 client pays $0.10 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": "payroll-batch",
  "input": {
    "employees": [
      {
        "id": "kim",
        "annualSalary": 40000000
      },
      {
        "id": "lee",
        "monthlySalary": 5000000,
        "dependents": 3,
        "children8to20": 1
      }
    ]
  },
  "result": {
    "headcount": 2,
    "totals": {
      "grossMonthly": 8333333,
      "netMonthly": 7259043,
      "employeeDeductions": 1074290,
      "incomeTaxWithheld": 275840,
      "localIncomeTaxWithheld": 27580,
      "employeeInsurance": 770870,
      "employerInsurance": 790710,
      "employerCost": 9124043
    },
    "employees": [
      {
        "id": "kim",
        "grossMonthly": 3333333,
        "netMonthly": 2935813,
        "employeeDeductions": 397520,
        "deductions": {
          "nationalPension": 148810,
          "healthInsurance": 112640,
          "longTermCare": 14800,
          "employmentInsurance": 28190,
          "incomeTax": 84620,
          "localIncomeTax": 8460
        },
        "employerInsurance": 312280,
        "employerCost": 3645613
      },
      {
        "id": "lee",
        "grossMonthly": 5000000,
        "netMonthly": 4323230,
        "employeeDeductions": 676770,
        "deductions": {
          "nationalPension": 228000,
          "healthInsurance": 172560,
          "longTermCare": 22670,
          "employmentInsurance": 43200,
          "incomeTax": 191220,
          "localIncomeTax": 19120
        },
        "employerInsurance": 478430,
        "employerCost": 5478430
      }
    ]
  }
}

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