Library of Congress · Rate Limits
Loc Rate Limits
The Library of Congress enforces rate limits per service to ensure equitable access. Exceeding limits triggers a 1-hour block for loc.gov JSON API endpoints. The Congress.gov API returns HTTP 429 when the hourly limit is reached.
Loc Rate Limits is the machine-readable rate-limit profile for Library of Congress on the APIs.io network, conforming to the API Commons Rate Limits specification.
Tagged areas include Library, Government, Congress, Legislative Data, and Digital Collections.
0 Limits
LibraryGovernmentCongressLegislative DataDigital CollectionsNewspapersMapsBibliographic RecordsHistorical Documents
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Every rate limit here is available over the APIs.io API and to AI agents over MCP.
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Tools for rate limits
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find_rate_limitsBrowse and filter every rate limit in the catalog.apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.resolveTurn a domain, URL or GitHub org into the provider it belongs to.find_cohortsEvery scored population of providers in the catalog.
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This rate limit
curl "https://apis.io/api/v1/rate-limits/loc-rate-limits"
All rate limits
curl "https://apis.io/api/v1/rate-limits?limit=25"Discovery needs no key. Ratings and market analysis are Pro.