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Homepage / Unpaywall – find free (and legal!) open access papers

Unpaywall – find free (and legal!) open access papers


People dancing in front of a lit up sign reading Free

Wouldn’t it be handy if you could easily check to see if there was an open access version of a paper that wasn’t available to you through the Library’s subscriptions? Well, Unpaywall could be just what you’re looking for!

Unpaywall finds free versions of paywalled papers from a database of about 10 million. The main difference between Unpaywall and Sci-Hub (which you may have used before), is that Unpaywall directs you to papers that authors have legally uploaded to free research repositories online (like CERES here at Cranfield). It has been developed by a nonprofit website called Impactstory, whose aim is to help researchers ‘explore and share the online impact of their work’ [1].

It will be officially released on Tuesday 4 April, but is available right now. To get it working you need to download an extension to your browser, and it is currently only available for the Firefox and Chrome browsers. I use Firefox, and you can see the little icon for it on my tool bar here (circled), sitting next to my Mendeley bookmarklet:


Once you’ve downloaded the extension, click on the icon and choose the ‘options’ cog. Select the ‘Colour-code tab for green and gold OA’ option. This means that you’ll see a green tab for a paper available via green Open Access, a gold one for gold Open Access, and a blue tab if we pay for you to access the paper through one of our Library subscriptions. This is how it looks once you have landed on a page containing the details of an article. The icon of the gold unlocked padlock shows that this is a gold OA version of the paper:


And here’s what a green OA paper looks like:


Just click on the padlock to view the full text.

For more information and to download the browser extension go to

Public domain image from


[1] Impactstory (Undated) About. Available from: (Accessed 28th March 2017).

Written By: Emma Turner

Emma is a Research Information Specialist based in the Kings Norton Library at Cranfield University.

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