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Developer Resources

Reader Aids

Reader Aids help people use and understand the federal rulemaking process. Reader Aids information is not published in the Federal Register.

This section of our Reader Aids is designed for anyone who wants to use Federal Register data programmatically. Explore our API interactively, get details about all of our API endpoints, and more.

Reader aid items in this section

  • REST API & Interactive Documentation

    Federal Register data originates with the files used to produce the print and PDF editions. During the publication process these are transformed into bulk XML files made available by the Government Publishing Office (GPO). Additional MODS files that contain metadata about each document are also produced at the same time. Because these files are meant … Continue reading “REST API & Interactive Documentation”

  • API Clients

    Ruby API Client The team maintains a Ruby API client that is available as a Ruby gem. This client gem is used to power the web display of You can find it on GitHub and RubyGems. Other resources To learn more about our API you can read more here and explore the API with … Continue reading “API Clients”

  • is Open Source

    Project Source Code is a fully open source project and its source code is available on Github. The source code is available in two repositories. The first, federalregister-api-core, contains the code that powers the import of Federal Register data from various sources and serves our API responses. This repo is undergoing active cleanup … Continue reading “ is Open Source”

  • Bulk Data

    Bulk data is currently only available in XML format. The U.S. Government Publishing Office (GPO) and the National Archives’ Office of the Federal Register (OFR) partnership is offering bulk data downloads of Federal Register XML files to the general public via and FDsys at Information on the legal status, authenticity, and schema of … Continue reading “Bulk Data”

  • API Case Study

    One of the difficulties for anyone seeking to use government data is to match up datasets from various Federal sources. Identifiers such as field names and agency name references often are not identical. Further, the data is often complex and requires a fair amount of understanding of agency processes to create a coherent whole. On August … Continue reading “ API Case Study”