scholarly-metadata
OpenAlex
An open index of the global research landscape: about 480 million scholarly works linked to authors, institutions, and topics. You can explore it at openalex.org or query its API, which since February 2026 requires a free account key (with a substantial free daily allowance). Strong for broad literature mapping — works, authors, and institutional output in one place. Keyless access is now limited to a small daily demo quota.
Why it’s useful & how it works
2026 CHANGE: API key REQUIRED since 13 Feb 2026 (free account, $1/day free, 100k calls/day); keyless = ~100 demo credits/day then 409. Probe returned 200 on demo credits. Provision a key before launch.
What’s inside
~480M works.
API access
https://api.openalex.org/works/doi: <doi> ; filter/search params
An API key is required — usually free; see the endpoints above for where to get one.
Access
Programmatic API access (a key may be required — see the API tag).