National Center for Biotechnology Information (NCBI)

NCBI Entrez E-utilities API

The Entrez Programming Utilities (E-utilities) are the public API to the NCBI Entrez system, providing access to over 38 Entrez databases including PubMed, GenBank (Nuccore), Gene, Taxonomy, and Protein. Nine server-side programs support text search, record retrieval, batch download, database linking, spelling correction, and citation matching. Requests can be authenticated with an API key to raise rate limits from 3 to 10 requests per second.

GitHub

Documentation

📖
Documentation
https://www.ncbi.nlm.nih.gov/books/NBK25497/
📖
GettingStarted
https://www.ncbi.nlm.nih.gov/books/NBK25500/
📖
RateLimits
https://kinlane.github.io/ncbi/rate-limits/e-utilities.yml

Other Resources

🔗
Plans
https://kinlane.github.io/ncbi/plans/e-utilities.yml
🔗
APIsJSON
https://raw.githubusercontent.com/api-evangelist/ncbi/refs/heads/main/apis.yml

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API entry from apis.yml

apis.yml Raw ↑ 
name: NCBI Entrez E-utilities API
description: 'The Entrez Programming Utilities (E-utilities) are the public API to the NCBI Entrez system,
  providing access to over 38 Entrez databases including PubMed, GenBank (Nuccore), Gene, Taxonomy, and
  Protein. Nine server-side programs support text search, record retrieval, batch download, database linking,
  spelling correction, and citation matching. Requests can be authenticated with an API key to raise rate
  limits from 3 to 10 requests per second.

  '
image: https://www.ncbi.nlm.nih.gov/favicon.ico
humanURL: https://www.ncbi.nlm.nih.gov/books/NBK25497/
baseURL: https://eutils.ncbi.nlm.nih.gov/entrez/eutils/
tags:
- Entrez
- PubMed
- GenBank
- Gene
- Taxonomy
- Sequences
- Literature
properties:
- type: Documentation
  url: https://www.ncbi.nlm.nih.gov/books/NBK25497/
- type: GettingStarted
  url: https://www.ncbi.nlm.nih.gov/books/NBK25500/
- type: RateLimits
  url: https://kinlane.github.io/ncbi/rate-limits/e-utilities.yml
- type: Plans
  url: https://kinlane.github.io/ncbi/plans/e-utilities.yml
contact:
- FN: NCBI E-utilities Support
  email: vog.hin.mln.ibcn@seitilitue
  url: https://support.nlm.nih.gov/support/create-case/