API Reference | seqout

API ReferenceThe seqout API provides programmatic access to over 1 million GEO, SRA, ENA & ArrayExpress projects. All endpoints are free, require no authentication, and return JSON unless noted otherwise.

Base URL: https://seqout.org/api — Interactive Swagger docs at https://seqout.org/api/docs — For LLM integration see the MCP Server

Search Projects Experiments & Samples Downloads Statistics Lookup & Resolution

GET/searchSearch all databases

GET/search/geoSearch GEO only

GET/search/sraSearch SRA only

GET/search/structuredStructured search with metadata filters

Projects

GET/project/{accession}Get project metadata

GET/project/{accession}/metadataGet project title and description

GET/project/{accession}/xrefCross-reference lookup

GET/project/{accession}/citeGet BibTeX citation

GET/project/{accession}/enrichedAI-enriched sample metadata

Experiments & Samples

GET/project/{study}/experimentsList study experiments

GET/project/{study}/runsList FASTQ download links

GET/sample/{accession}Get sample metadata

GET/sample-detail/{accession}Get full sample detail

GET/geo/series/{accession}/samplesList GEO/ArrayExpress samples

Downloads

GET/project/{study}/runs/downloadDownload run links as TSV

GET/project/{study}/metadata/downloadDownload merged metadata CSV

GET/project/{study}/download/{mode}Download bash script

GET/project/{accession}/supplementary/downloadDownload supplementary files script

POST/bulk/metadataBulk metadata download

POST/bulk/project-metadataBulk project metadata lookup

Statistics

GET/stats/growthDatabase growth over time

GET/stats/organism-growthOrganism growth over time

GET/stats/organism-totalsTotal experiments per organism

GET/stats/organism-searchSearch organisms by name

GET/stats/global-contributionsGeographic contributions

GET/stats/global-contributions/accessionsAccessions by country

Lookup & Resolution

GET/accession/{accession}/projectResolve accession to parent project

GET/prj/{prj_accession}Resolve BioProject to study

GET/common-nameGet common name for organism

GET/organismsList all organisms

Rate LimitsMost endpoints allow 60 requests/minute per IP. Search endpoints allow 30 requests/minute. Bulk and download endpoints allow 10 requests/minute. Responses include standard rate limit headers.

PaginationSearch endpoints use cursor-based pagination. Each response includes a next_cursor object. Pass its fields as query parameters to fetch the next page. When next_cursor is null, there are no more results.

# First page
curl "https://seqout.org/api/search?q=CRISPR"

# Next page (use next_cursor from response)
curl "https://seqout.org/api/search?q=CRISPR&cursor_rank=0.12&cursor_acc=GSE123456"