US Census Bureau Data API

US Census Bureau Data API

The U.S. Census Bureau's Data API exposes the American Community Survey, decennial census, economic census, international trade and other Census Bureau statistical series as JSON over HTTPS. A free API key is required; the checked unauthenticated request returned a 'Missing Key' response.

Coverage

The Terms of Service page describes permitted use: "You may use the Census Bureau API to develop a service or service to search, display, analyze, retrieve, view and otherwise "get" information from Census Bureau data." Figures are disclosure-avoided statistics under 13 U.S.C. §§ 8 and 9, which bar using the data, alone or combined with other data, to identify a respondent. Per-endpoint coverage years, geographies and update schedules vary by dataset; the checked example queried the 2023 ACS 1-year estimates. History start and update frequency across all datasets: Not stated as a single figure.

Verdict

Use this for US demographic and economic statistics (ACS, decennial and economic census, international trade and more) through one JSON API with a free key. The terms page requires an endorsement disclaimer and bars implying endorsement: "You may not use the Census Bureau name, or the like to imply endorsement of any product, service, or entity, not-for-profit, commercial or otherwise." It also reserves a 'Right to Limit' on access, calls or use without stating a numeric rate, and the figures are disclosure-avoided aggregates under 13 U.S.C. §§ 8 and 9, not microdata. Signal Lab links only.