Korea Payroll & Tax API › year-end-tax-batch

South Korea year-end tax settlement estimate for up to 100 employees in one call

South Korea year-end tax settlement estimate for up to 100 employees in one call: refund or additional tax for each employee from salary, dependents, card spending and the main deductions, with totals. Same calculation as year-end-tax-settlement, without the per-employee breakdown.

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/year-end-tax-batch -H "content-type: application/json" \
  -d '{"employees":[{"id":"kim","grossSalary":50000000,"creditCard":15000000,"debitCash":5000000},{"id":"lee","grossSalary":80000000,"dependents":3,"children":1,"children8to20":1,"pensionSavings":6000000}]}'

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": "year-end-tax-batch",
  "input": {
    "employees": [
      {
        "id": "kim",
        "grossSalary": 50000000,
        "creditCard": 15000000,
        "debitCash": 5000000
      },
      {
        "id": "lee",
        "grossSalary": 80000000,
        "dependents": 3,
        "children": 1,
        "children8to20": 1,
        "pensionSavings": 6000000
      }
    ]
  },
  "result": {
    "headcount": 2,
    "refundCount": 1,
    "additionalPaymentCount": 1,
    "totals": {
      "refund": 110350,
      "additionalPayment": 174090,
      "finalIncomeTax": 8242310
    },
    "employees": [
      {
        "id": "kim",
        "outcome": "refund",
        "amount": 110350,
        "finalIncomeTax": 2507520,
        "localIncomeTax": 250750,
        "incomeTaxAlreadyWithheld": 2607840,
        "withheldIsEstimate": true,
        "effectiveRatePct": 5.5,
        "method": "itemized_special_deductions"
      },
      {
        "id": "lee",
        "outcome": "additional_payment",
        "amount": 174090,
        "finalIncomeTax": 5734790,
        "localIncomeTax": 573470,
        "incomeTaxAlreadyWithheld": 5576520,
        "withheldIsEstimate": true,
        "effectiveRatePct": 7.9,
        "method": "itemized_special_deductions"
      }
    ]
  }
}

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