NCBI Nucleotide API

Programmatic access to NCBI's Nucleotide database (nuccore) using the E-Utilities API. Provides search, summary, and full record retrieval for nucleotide sequences from GenBank, RefSeq, and other sources. Rate limits: 3 requests/second without API key, 10 requests/second with API key.

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Base URL: https://www.ncbi.nlm.nih.gov/nuccore/
Auth: none
Endpoints: 5
Reachable: yes
CORS: unknown
Last checked: 2026-03-14 16:08:49.330344

Links

Homepage: https://www.ncbi.nlm.nih.gov/
API Base: https://www.ncbi.nlm.nih.gov/nuccore/
Documentation:

100.0%

Uptime (7d)

1525ms

Avg latency (7d)

15

Probes (7d)

Latency (7d)

Success Rate (7d)

Topics

GENETICS, GENOMICS, SCIENCE

Endpoints

Method Path Summary Auth Last Status Latency
GET /efetch.fcgi Fetch full records — 200 2161ms
GET /einfo.fcgi Get database information — 200 460ms
GET /elink.fcgi Link to related records — 200 608ms
GET /esearch.fcgi Search nucleotide database — 200 951ms
GET /esummary.fcgi Get document summaries — 200 365ms