Data API - CountryTaxCalc | Global Tax Data for Developers

Overview

The CountryTaxCalc API provides accurate income tax data for 111 countries. All data is sourced from official government tax authorities and updated annually.

111 countries with progressive brackets, flat rates, and social contributions
US state tax included (50 states + DC)
Canadian provincial tax included (13 provinces/territories)
All responses in JSON with consistent structure
Rate limit: 100,000 requests/day

To request an API key, contact daniel@countrytaxcalc.com.

Authentication

All endpoints except /health require an API key, passed as a header:

X-API-Key: your_api_key_here

Or as a query parameter: ?api_key=your_api_key_here

Requests without a valid key return 401 Unauthorized.

Endpoints

GET /api/v1/health Public

Status check. No authentication required.

curl https://api.countrytaxcalc.com/api/v1/health

{
  "status": "healthy",
  "timestamp": "2026-04-15T12:00:00.000Z",
  "database": "connected"
}

GET /api/v1/countries

List all supported countries.

curl https://api.countrytaxcalc.com/api/v1/countries \
  -H "X-API-Key: your_key"

GET /api/v1/countries/{code}

Country metadata — currency, complexity, available jurisdictions.

curl https://api.countrytaxcalc.com/api/v1/countries/DE \
  -H "X-API-Key: your_key"

GET /api/v1/countries/{code}/rates New

Raw tax bracket data for a country — no income calculation required. Cached for 1 hour.

curl https://api.countrytaxcalc.com/api/v1/countries/DE/rates \
  -H "X-API-Key: your_key"

{
  "country_code": "DE",
  "country_name": "Germany",
  "currency": "EUR",
  "tax_year": 2026,
  "calculation_type": "progressive",
  "source_url": "https://www.bundesfinanzministerium.de/",
  "last_updated": "2026-04-15",
  "brackets": [
    { "from": 0, "to": 11784, "rate": 0, "rate_percent": "0.0%" },
    { "from": 11784, "to": 66761, "rate": 0.14, "rate_percent": "14.0%" },
    { "from": 66761, "to": null, "rate": 0.42, "rate_percent": "42.0%" }
  ],
  "deductions": [...],
  "social_contributions": [
    {
      "name": "Health Insurance (Employee)",
      "type": "health_employee",
      "employee_rate": 0.0735,
      "employer_rate": 0.0735,
      "cap_amount": null
    }
  ]
}

Optional query params: ?year=2026

POST /api/v1/calculate

Calculate tax for a specific income in a specific country. Returns full breakdown including deductions, social contributions, and net income.

curl -X POST https://api.countrytaxcalc.com/api/v1/calculate \
  -H "X-API-Key: your_key" \
  -H "Content-Type: application/json" \
  -d '{
    "country": "DE",
    "income": 80000,
    "currency": "EUR"
  }'

{
  "country": "Germany",
  "country_code": "DE",
  "tax_year": 2026,
  "currency": "EUR",
  "currency_symbol": "€",
  "currency_name": "Euro",
  "currency_conversion": {
    "input_income": 80000,
    "input_currency": "USD",
    "local_currency": "EUR",
    "exchange_rate": 0.9234,
    "converted_income": 73872,
    "rate_date": "2026-04-25",
    "fx_source": "frankfurter",
    "fx_rate_age_hours": 18.4
  },
  "gross_income": 73872,
  "breakdown": {
    "taxable_income": 62268,
    "deductions": [...],
    "national_income_tax": {
      "amount": 19843,
      "effective_rate": 26.86,
      "marginal_rate": 42,
      "brackets_applied": [...]
    },
    "social_contributions": [...]
  },
  "totals": {
    "total_tax": 25634,
    "net_income": 48238,
    "effective_tax_rate": 34.7,
    "take_home_percentage": 65.3,
    "monthly_net_income": 4019.8
  },
  "metadata": {
    "accuracy_confidence": 0.95,
    "data_source": "https://www.bundesfinanzministerium.de/",
    "last_updated": "2026-04-15"
  },
  "warnings": []
}

Note: currency_conversion only appears when the input currency differs from the country's local currency. The fx_source field is "frankfurter" (ECB, 30 currencies) or "exchangerate-api" (160+ currencies).

Field	Type	Required	Description
`country`	string	Yes	ISO 2-letter code (DE) or country name (Germany)
`income`	number	Yes	Annual gross income in local currency
`currency`	string	No	ISO 4217 code. If different from the country's local currency, auto-conversion is applied. Defaults to local currency.
`jurisdiction`	string	No	State/province code for US (CA), Canada (ON), etc.
`tax_year`	number	No	Defaults to current year

GET /api/v1/summary New

All 111 countries ranked by effective tax rate for a given income level. Useful for building country comparison tables.

curl "https://api.countrytaxcalc.com/api/v1/summary?income=100000" \
  -H "X-API-Key: your_key"

{
  "income": 100000,
  "currency_note": "Income treated as nominal in each country's local currency.",
  "tax_year": 2026,
  "total_countries": 111,
  "countries": [
    {
      "rank": 1,
      "country_code": "AE",
      "country_name": "United Arab Emirates",
      "currency": "AED",
      "income_tax": 0,
      "social_tax": 0,
      "total_tax": 0,
      "net_income": 100000,
      "effective_tax_rate": 0,
      "effective_tax_rate_percent": "0.0%"
    },
    ...
  ]
}

Optional query params: ?year=2026

Note: Income is treated as a nominal figure in each country's local currency. This endpoint is designed for relative tax burden comparisons, not absolute take-home pay comparisons across currencies.

POST /api/v1/compare

Compare tax burden across multiple specific countries for the same income.

curl -X POST https://api.countrytaxcalc.com/api/v1/compare \
  -H "X-API-Key: your_key" \
  -H "Content-Type: application/json" \
  -d '{
    "income": 100000,
    "currency": "USD",
    "countries": [
      { "country": "US", "jurisdiction": "CA" },
      { "country": "GB" },
      { "country": "DE" },
      { "country": "SG" }
    ]
  }'

Country Codes

Use standard ISO 3166-1 alpha-2 codes (e.g. GB, DE, JP). Country names also accepted (e.g. Germany).

For US state tax, pass "country": "US" with "jurisdiction": "CA" (California), "TX" (Texas), etc.

For Canadian provincial tax, pass "country": "CA" with "jurisdiction": "ON" (Ontario), "BC", etc.

accuracy_confidence

Every /calculate response includes metadata.accuracy_confidence:

Value	Meaning
`0.95`	DB-backed — sourced directly from official government tax authority
`0.70`	JS fallback — built-in data, may be less current

Attribution

API usage requires a visible attribution link near any displayed tax data:

<a href="https://www.countrytaxcalc.com" rel="dofollow">
  Powered by CountryTaxCalc.com
</a>

Get Access

The API is available to partners and developers. Email daniel@countrytaxcalc.com with a brief description of your use case.

CountryTaxCalc Data API