Unpaywall is a service developed by a non-profit organization that allows you to find open access versions of the articles you are currently consulting: over 25 million articles (legally obtained from over 50,000 institutional repositories and publisher websites) - published version; manuscript submitted to the publisher; or peer-reviewed manuscript - are available.

It makes it easy to find open-access versions of articles that would normally have to be paid for. Unpaywall can be used as an extension for Google Chrome or Firefox.

To use Unpaywall, you need to add the extension to Google Chrome or Firefox. This can be done from the software's website or from browser extension repositories. Once installed in the browser, the symbol will appear in the Google toolbar (a padlock on a black background). When searching for an article on the web, a padlock will appear on the right-hand side of the browser screen. If the article has an open version, the padlock background will be green, but if it's not available, the background will be grey. If the article is found and available, a click on the padlock will open a new tab with the PDF article ready to be read or saved on the computer.

Unpaywall is integrated into many databases, such as Scopus or Web of Science, and into Zotero.

To access: https: //unpaywall.org/

For more information: https: //unpaywall.org/faq