The one-click route to a legal free copy — and the open-access backbone behind other tools.
At a Glance
| Publisher | OurResearch (the US nonprofit behind OpenAlex) |
| Coverage | ~57M free scholarly articles with open full-text links, drawn from 50,000+ publishers and repositories, across 120M+ DOI-assigned articles |
| Access | free — a browser extension, an open REST API, and a full data feed |
| Regional | global. |
Our Take
Unpaywall does one thing extremely well: given a paper, it finds a legal, free, full-text version if one exists — via the browser extension for humans and the API for machines. It’s become quiet infrastructure for open science, feeding OA-status data into OpenAlex, library systems, and discovery tools, so you’re often using it without knowing. It only finds genuinely open copies (no paywalled or pirated content), which is the point, and coverage tracks whatever is legitimately OA. Install the extension for everyday reading; use the API to enrich a dataset with open-access status and links at scale.
Power Tips
- Install the browser extension so a free full-text copy is one click from any article page before you hit a paywall
- use the API to batch-annotate a reference list with open-access status and links; it pairs naturally with the OpenAlex data you may already pull (both are OurResearch).
Alternatives & Complements
OpenAlex · OpenAIRE · CORE · Google Scholar.
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