The Browser Plug-in That Lets You Access Millions of Scientific Papers for Free

The Browser Plug-in That Lets You Access Millions of Scientific Papers for Free

Here at Born to Engineer we try our best to link to original sources and supporting papers for breaking news. It can be frustrating when these are hidden behind a paywall – especially when work has been publicly funded and is intended to be freely accessible by its authors.

We think that knowledge should be accessible to as many people as possible. Unpaywall believes the same – it is a free browser extension is promising to bust through those paywalls wherever possible and completely shake up the world of Academic Publishing.


Unpaywall launched earlier this month and was created by the open source not-for-profit Impactstory and funded by the National Science Foundation and the Alfred P. Sloan Foundation.

Now more than ever, humanity needs to access our collective knowledge, not hoard it behind paywalls. Lots of researchers feel the same; that’s why they upload their papers to free, legal servers online. We want to help bring that open access content to the masses.

How Does Unpaywall Work?

The plugin works by searching for a freely accessible full-text copy of the paper you’re looking at, and if it finds it the lock symbol turns from grey to green, and you can click on it to get the PDF.

If the lock is gold, the article you’re reading already has an open access licence.

Is Unpaywall legal?

The plugin is able to function by searching thousands of existing open-access repositories worldwide.

It relies on a number of data sources, including PubMed Central, the DOAJ, Crossref (particularly their license info), DataCite, Google Scholar, and BASE.

By combining those sources Unpaywall has created (what it calls an) oaDOI API. Unpaywall describe this as “a free, fast, and very scalable way to leverage our data and infrastructure to support your own projects”.

As the plugin is searching existing open-access repositories and all the content on them is free and legally available. This is because a lot of researchers feel their work should be free to begin with. Many upload their papers to free, legal servers online as well as publishing in journals.

Install the plugin and find out more at

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