api.data.gov
Free API management gateway operated by the U.S. General Services Administration's Technology Transformation Services. Fronts the API keys, rate limiting, and analytics for over 450 APIs across roughly 25 participating federal agencies and serves as GSA's vehicle for fulfilling the Open Government Data Act of 2018. A single api.data.gov key is reusable across NASA, NREL, USDA, USDOT, Department of Education, Regulations.gov, GovInfo, and many other federal API surfaces.