API archive entry · source-reported
Unpaywall
Open-access status and legal full-text links for scholarly articles
Other Science & Math APIs
These records share a directory category and are ordered by similarity of reported access facts. They are a shortlist, not proof of drop-in compatibility.
DataCite
Search and retrieve DOI metadata for research datasets and publications
No auth · HTTPS reported · CORS Yes
Solar System OpenData
Data and facts on solar system bodies and planets
No auth · HTTPS reported · CORS Yes
GBIF
Global Biodiversity Information Facility
No auth · HTTPS reported · CORS Yes
Unusual Units Converter
Unit converter for standard and uncommon units
No auth · HTTPS reported · CORS Yes
CycleCalcs
Interpreted astronomy: sun and moon times, moon phases, planets, eclipses, seasons
No auth · HTTPS reported · CORS Yes
Europe PMC
Life-science literature search with abstracts, citations and full-text links
No auth · HTTPS reported · CORS Yes
How to compare them
Coverage
Compare exact endpoints, fields, geography, history, and update frequency.
Operating cost
Model request volume, caching, overages, support, and migration cost.
Integration risk
Test auth, errors, pagination, latency, versioning, and outage behavior.
Data rights
Review attribution, redistribution, retention, privacy, and commercial-use terms.
Source reference
This page separates source-reported facts from questions that need live provider verification.