Demographic Data API

• One schema for every source. World Bank, UN, Eurostat, the US Census and more, normalised to the same geography ids, units and years.
• Provenance on every response. Source, licence and the attribution line you must show — per value, not per dataset.
• Honest coverage. Each series lists the years it is missing. We never interpolate or fill gaps, and forecasts are marked as projections.
• Licence-safe by default. Values whose licence forbids resale are withheld and counted, so you see the gap instead of inheriting a legal problem.
• Bulk files and time series. Pull one country's history or every value of an indicator as CSV.

Built for market sizing, actuarial and pension models, school and maternity-care planning, academic research and newsroom data desks.

curl "https://birthrate.io/api/v1/data?indicator=fertility-rate&id=JPN,KOR&from=2015" \
  -H "X-API-Key: $BIRTHRATE_KEY"

{
  "data": [{
    "geography": { "level": "country", "id": "JPN", "name": "Japan" },
    "coverage": { "from": 2015, "to": …, "observations": …, "missingYears": [] },
    "observations": [{ "year": 2015, "value": …, "kind": "estimate", "source": "WORLD_BANK" }, …]
  }, …],
  "meta": {
    "indicator": { "slug": "fertility-rate", "unit": "births per woman", … },
    "availability": { "geographies": 2, "values": …, "withheld": [] },
    "sources": [{ "code": "WORLD_BANK", "license": "CC BY 4.0", "attribution": "World Bank, …" }],
    "apiVersion": "2026-10-24", "citation": "birthrate.io (2026), compiled from the sources listed."
  }
}