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OpenAlex API

Open catalog of 250M+ works, authors and institutions, free key, $1/day free

OpenAlex is a fully open index of the global research ecosystem: hundreds of millions of works, authors, journals, institutions and topics, openly licensed (CC0). The REST API is all GET requests you can paste into a browser. As of 2025 it requires a free key, and every key gets $1 of usage credit per day, which covers large free volumes.

Free tier

Free key; each key gets $1/day free credit (~100,000 credits/day, covering large free volumes). Full dataset is CC0 and free to bulk-download

Rate limits

Free key: up to 100,000 credits/day. No key: hard-capped at 100 credits/day, for testing only

Auth

API key

Base URL

https://api.openalex.org

What you'd build with it

  • Build a free alternative to commercial citation databases
  • Map an institution's or author's full publication output
  • Filter works by topic and year for a research-trends automation
  • Enrich DOIs with open-access status and citation counts

Key endpoints

  • GET/works?search={q}Search the index of scholarly works
  • GET/works/{id}Full metadata for one work (DOI, OpenAlex ID, etc.)
  • GET/authors?search={name}Find authors and their disambiguated profiles
  • GET/works?filter=concepts.id:{id}Filter works by topic, year, institution and more
Members

Members get the runnable recipe

Sign in free to copy the example request, see a sample response, and read the gotchas.

Tags

knowledgeresearchpaperscitationsreference