ClinicalTrials.gov

aid: clinical-trials-gov
name: ClinicalTrials.gov
description: ClinicalTrials.gov is the U.S. National Institutes of Health (NIH) registry and results database of publicly
  and privately supported clinical studies of human participants conducted around the world. Operated by the National Library
  of Medicine (NLM), it provides a modern REST API (data-api v2) that returns study records, study metadata, search areas,
  and field definitions in JSON. The predecessor classic API remains available for legacy consumers but is being phased out
  in favor of the v2 API. Data is in the public domain and freely accessible without authentication.
type: Index
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/clinical-trials-gov.png
url: https://raw.githubusercontent.com/api-evangelist/clinical-trials-gov/refs/heads/main/apis.yml
created: '2024-01-01'
modified: '2026-04-23'
specificationVersion: '0.19'
kind: government
tags:
- Clinical Trials
- Government
- Health
- NIH
- Open Data
- Public Health
- Research
apis:
- aid: clinical-trials-gov:classic-api
  name: ClinicalTrials.gov Classic API
  tags:
  - Clinical Trials
  - Legacy
  - REST
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  baseURL: https://clinicaltrials.gov/api
  humanURL: https://clinicaltrials.gov/data-api/api
  properties:
  - url: https://clinicaltrials.gov/data-api/api
    type: Documentation
  description: The Classic API is the legacy ClinicalTrials.gov interface that preceded the Data API v2 and exposes full-study,
    brief-study, and field-values endpoints with XML, JSON, and CSV responses. It is being deprecated in favor of the v2 REST
    API and remains online for backward compatibility while consumers migrate.
- aid: clinical-trials-gov:bulk-downloads
  name: ClinicalTrials.gov Bulk Downloads
  tags:
  - Bulk
  - Datasets
  - Open Data
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://clinicaltrials.gov/data-api/about-api/csv-download
  properties:
  - url: https://clinicaltrials.gov/data-api/about-api/csv-download
    type: Documentation
  description: ClinicalTrials.gov provides bulk CSV and JSON downloads of the full study registry through the data-api download
    endpoints. These artifacts support large-scale analytics, archival, and offline mirrors of the registry without making
    per-record API calls.
- aid: clinical-trials-gov:aact
  name: AACT Database
  tags:
  - Analytics
  - Database
  - Postgres
  - Research
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://aact.ctti-clinicaltrials.org/
  properties:
  - url: https://aact.ctti-clinicaltrials.org/
    type: Documentation
  - url: https://aact.ctti-clinicaltrials.org/data_dictionary
    type: Data Dictionary
  description: AACT (Aggregate Analysis of ClinicalTrials.gov) is a publicly available relational database of all ClinicalTrials.gov
    study content maintained by the Clinical Trials Transformation Initiative (CTTI) at Duke University. It is updated daily
    and is widely used by researchers as a SQL-friendly mirror of the registry.
- aid: clinical-trials-gov:clinical-trials-gov-stats-api
  name: ClinicalTrials.gov Stats API
  description: The Stats API from ClinicalTrials.gov — 3 operation(s) for stats.
  humanURL: https://clinicaltrials.gov/data-api/api
  baseURL: https://clinicaltrials.gov/api/v2
  tags:
  - Stats
  properties:
  - type: OpenAPI
    url: openapi/clinical-trials-gov-stats-api-openapi.yml
  - type: Documentation
    url: https://clinicaltrials.gov/data-api/api
  - type: About
    url: https://clinicaltrials.gov/data-api/about-api
- aid: clinical-trials-gov:clinical-trials-gov-studies-api
  name: ClinicalTrials.gov Studies API
  description: The Studies API from ClinicalTrials.gov — 5 operation(s) for studies.
  humanURL: https://clinicaltrials.gov/data-api/api
  baseURL: https://clinicaltrials.gov/api/v2
  tags:
  - Studies
  properties:
  - type: OpenAPI
    url: openapi/clinical-trials-gov-studies-api-openapi.yml
  - type: Documentation
    url: https://clinicaltrials.gov/data-api/api
  - type: About
    url: https://clinicaltrials.gov/data-api/about-api
- aid: clinical-trials-gov:clinical-trials-gov-version-api
  name: ClinicalTrials.gov Version API
  description: The Version API from ClinicalTrials.gov — 1 operation(s) for version.
  humanURL: https://clinicaltrials.gov/data-api/api
  baseURL: https://clinicaltrials.gov/api/v2
  tags:
  - Version
  properties:
  - type: OpenAPI
    url: openapi/clinical-trials-gov-version-api-openapi.yml
  - type: Documentation
    url: https://clinicaltrials.gov/data-api/api
  - type: About
    url: https://clinicaltrials.gov/data-api/about-api
common:
- type: AgenticAccess
  url: agentic-access/clinical-trials-gov-agentic-access.yml
- type: DomainSecurity
  url: security/clinical-trials-gov-domain-security.yml
- type: Website
  url: https://clinicaltrials.gov/
- type: About
  url: https://clinicaltrials.gov/about-site
- type: Documentation
  url: https://clinicaltrials.gov/data-api/api
- type: Portal
  url: https://clinicaltrials.gov/data-api
- type: Glossary
  url: https://clinicaltrials.gov/study-basics/glossary
- type: News
  url: https://clinicaltrials.gov/about-site/announcements
- type: Help
  url: https://clinicaltrials.gov/help
- type: PrivacyPolicy
  url: https://www.nlm.nih.gov/privacy.html
- type: TermsOfService
  url: https://clinicaltrials.gov/about-site/terms-conditions
- type: GitHub
  url: https://github.com/clinicaltrialsgov
- type: JSONLD
  url: json-ld/clinical-trials-gov-context.jsonld
- type: Spectral
  url: rules/clinical-trials-gov-rules.yml
- type: LlmsText
  url: https://clinicaltrials.gov/llms.txt
maintainers:
- FN: Kin Lane
  email: kinlane@gmail.com