Library of Congress

aid: loc
name: Library of Congress
description: The Library of Congress is the largest library in the world and the research arm of the US Congress. It provides REST APIs for accessing digitized collections, Congress.gov legislative data, bibliographic records, historic newspapers via Chronicling America, maps, photographs, manuscripts, and historical government documents. The loc.gov JSON API requires no authentication, while the Congress.gov API requires a free API key.
image: https://kinlane-productions.s3.amazonaws.com/apis-json/apis-json-logo.jpg
url: https://raw.githubusercontent.com/api-evangelist/loc/refs/heads/main/apis.yml
created: '2026-06-13'
modified: '2026-06-13'
specificationVersion: '0.19'
type: Index
tags:
  - Library
  - Government
  - Congress
  - Legislative Data
  - Digital Collections
  - Newspapers
  - Maps
  - Bibliographic Records
  - Historical Documents
apis:
  - name: loc.gov JSON API
    description: The loc.gov JSON/YAML API provides structured, machine-readable data about Library of Congress digital collections — books, photographs, maps, manuscripts, archived websites, videos, and more. No authentication is required. Responses are available in JSON or YAML format via the fo= query parameter.
    image: https://kinlane-productions.s3.amazonaws.com/apis-json/apis-json-logo.jpg
    humanURL: https://www.loc.gov/apis/json-and-yaml/
    baseURL: https://www.loc.gov
    tags:
      - Collections
      - Digital Library
      - JSON
      - YAML
      - Search
    properties:
      - type: Documentation
        url: https://www.loc.gov/apis/json-and-yaml/
      - type: OpenAPI
        url: openapi/loc-loc-gov-json-api-openapi.yml
    contact:
      - FN: Library of Congress
        url: https://www.loc.gov/about/contact-us/
  - name: Congress.gov API
    description: The Congress.gov API (v3) provides machine-readable access to legislative data from Congress.gov, including bills, amendments, summaries, members, committees, nominations, treaties, and the Congressional Record. Responses are available in JSON or XML. A free API key is required (sign up at api.congress.gov). Rate limit is 5,000 requests per hour.
    image: https://kinlane-productions.s3.amazonaws.com/apis-json/apis-json-logo.jpg
    humanURL: https://api.congress.gov/
    baseURL: https://api.congress.gov/v3
    tags:
      - Congress
      - Legislative Data
      - Bills
      - Amendments
      - Members
      - Committees
      - Nominations
      - Treaties
    properties:
      - type: Documentation
        url: https://api.congress.gov/
      - type: GithubRepository
        url: https://github.com/LibraryOfCongress/api.congress.gov
      - type: Signup
        url: https://api.congress.gov/sign-up/
      - type: OpenAPI
        url: openapi/loc-congress-gov-openapi.yml
    contact:
      - FN: Library of Congress
        url: https://www.loc.gov/about/contact-us/
  - name: Chronicling America API
    description: The Chronicling America API provides access to the historic American newspapers collection digitized by the Library of Congress and its partners. Endpoints allow searching and retrieving pages, titles, batches, and OCR text. No authentication is required.
    image: https://kinlane-productions.s3.amazonaws.com/apis-json/apis-json-logo.jpg
    humanURL: https://chroniclingamerica.loc.gov/about/api/
    baseURL: https://chroniclingamerica.loc.gov
    tags:
      - Newspapers
      - Historical
      - Digitized
      - Search
      - OCR
    properties:
      - type: Documentation
        url: https://chroniclingamerica.loc.gov/about/api/
    contact:
      - FN: Library of Congress
        url: https://www.loc.gov/about/contact-us/
common:
  - type: Website
    url: https://www.loc.gov
  - type: Documentation
    url: https://www.loc.gov/apis/
  - type: GitHubOrg
    url: https://github.com/LibraryOfCongress
  - type: LinkedIn
    url: https://www.linkedin.com/company/library-of-congress
  - type: Blog
    url: https://blogs.loc.gov/thesignal/
  - type: Pricing
    url: https://www.loc.gov/apis/
  - type: StatusPage
    url: https://uptime.com/upstatus/loc.gov
  - type: X
    url: https://twitter.com/librarycongress
  - type: Plans
    url: plans/loc-plans-pricing.yml
  - type: RateLimits
    url: rate-limits/loc-rate-limits.yml
  - type: FinOps
    url: finops/loc-finops.yml
maintainers:
  - FN: Kin Lane
    email: [email protected]