National Center for Biotechnology Information (NCBI) · Pricing Plans

E Utilities

The NCBI E-utilities API is free to use. Access tiers are differentiated by API key registration. All plans are no-cost; the API key raises the per-second rate limit and enables higher-volume access upon request.

E Utilities is the machine-readable pricing-plan profile for National Center for Biotechnology Information (NCBI) on the APIs.io network, conforming to the API Commons Plans specification.

It defines 2 plans, with named plans including Anonymous (No API Key), Registered API Key.

Tagged areas include Bioinformatics, Genomics, Life Sciences, PubMed, and Sequences.

2 Plans
View Source
BioinformaticsGenomicsLife SciencesPubMedSequencesBLASTTaxonomyChemistryOpen Access

Plans

Anonymous (No API Key)

Unauthenticated access to all nine E-utilities endpoints. Suitable for interactive queries and low-volume integrations. No registration required.

Registered API Key

Free API key obtained from NCBI account settings. Raises the default rate limit to 10 requests per second. Higher limits are available upon request by emailing NCBI. Requires registering a tool name and contact email in request parameters.

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Tools for plans

4 MCP tools reach this
  • find_plansBrowse and filter every plan in the catalog.
  • apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
  • resolveTurn a domain, URL or GitHub org into the provider it belongs to.
  • find_cohortsEvery scored population of providers in the catalog.
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Call it yourself

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This plan 
curl "https://apis.io/api/v1/plans/e-utilities"
All plans 
curl "https://apis.io/api/v1/plans?limit=25"

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