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eCFR

eCFR Versioner Service API

Access CFR content and structure files through JSON and XML

Documentation Provider Profile APIs.io OpenAPI GitHub

eCFR Versioner Service API is one of 3 APIs that eCFR publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

Tagged areas include Versioner Service. The published artifact set on APIs.io includes an OpenAPI specification and API documentation.

This API exposes 5 operations across 5 paths. It is described by OpenAPI 3.2.0.

Requests are made against a single base URL, https://www.ecfr.gov.

5 operations 5 paths 0 schemas 5 GET

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.2.0
Base URL
https://www.ecfr.gov/api/versioner/v1
Resource Areas
1

Paths & Operations 5

Across 5 paths, the API surfaces 5 operations — 5 GET. Each is listed below with its method, path, parameters, and response codes.

Versioner Service 5

Access CFR content and structure files through JSON and XML

GET
/api/versioner/v1/ancestry/{date}/title-{title}.json
Ancestors route returns all ancestors (including self) from a given level through the top title node.
9 params → 200404
GET
/api/versioner/v1/full/{date}/title-{title}.xml
Source XML for a title or subset of a title. Requests can be for entire titles or part level and below. Downloadable XML document is returned for title requests. Processed XML is returned if part, su…
9 params → 200400404
GET
/api/versioner/v1/structure/{date}/title-{title}.json
Structure JSON for a title
2 params → 200404
GET
/api/versioner/v1/titles.json
Summary information about each title
→ 200
GET
/api/versioner/v1/versions/title-{title}.json
Returns an array of all sections and appendices inside a title.
12 params → 200400503

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

ecfr-versioner-service-api-openapi.yml Raw ↑

Other APIs eCFR publishes across the network.

eCFR Admin Service API
AE Profile APIs.io
eCFR Search Service API
AE Profile APIs.io
#Versioner Service
← Back to E APIs
API Details
ID
ecfr:ecfr-versioner-service-api
Base URL
https://www.ecfr.gov/api/versioner/v1
Docs
https://www.ecfr.gov/developers/documentation/api/v1
Provider
eCFR
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