Here at JHU, Open Access Week 2018 supported the new Johns Hopkins Open Access Policy and the Public Access Submission System. The policy and tool help faculty make their research openly available, reaching individuals that aren’t associated with a research library.

Today I want to talk about how to find those openly available research articles. If you’re a student you will leave JHU at some point and that means you won’t have access to our extensive library collection. You’ll need open access then. Perhaps you are interested in Open Access as a social justice issue and wish to utilize openly available articles in your own research right now. The Library can help with that! Below are groups of tools and resources that can help you find Open Articles about a topic. I’ve grouped these into Library Databases, Repositories, Open Access Databases, and Apps. Let me know if you find other resources that point to open access articles. I’ve also summarized all this on a guide page for your continued use.

Library Databases

Since many research funders and institutions require articles to be openly available, many library databases index Open Access journals like PLOS Biology, Nature Communications, and Sociological Science. While many databases include OA journals, they don’t all give you an easy way to limit a search to just OA articles. The databases below let you limit to Open Access articles.

  • Scopus – Once you have a result list, click the Open Access box under Access Type in the left column.
  • Web of Science – Once you have a result list, click the Open Access box under Filter by in the left column.
  • PubMed – Once you have a result list, click ‘Free full text’ under Text Availability in the left column.


Some disciplines and funding agencies have repositories whose purpose is to openly and freely share research. These repositories offer a variety of types of articles. Without getting into a lot of detail, the article types include:

  • Preprint – an article that hasn’t gone through peer review at a journal.
  • Postprint – an article that has gone through peer review, but doesn’t include the final copyediting and page numbering from the journal. This is also referred to as the author’s final version/manuscript.
  • Version of record – the article as it appeared in the journal; it has been peer reviewed and copyedited. This is also referred to as the published article.

Two of the best known repositories are

  • arXiv is the oldest repository, hosting articles on physics, mathematics, computational biology, and other fields of research. Preprints, postprints, and published papers are available here.
  • PubMed Central is run by the National Institutes of Health. The NIH requires articles resulting from their funding to be openly available 12 months after it’s been published. The articles in PMC are either postprints or the version of record.

There are plenty of other repositories out there. Take a peek at OpenDOAR, the directory of open access repositories.

Open Access Databases

I only know about one database built entirely of open research articles, listed below. As I stated above, most of the library databases – and Google Scholar too – include open access articles. Only a few let you limit a results list to Open Access with a click. You can also go to a relevant repository and search just the articles in that database. But if you want to search across all the open literature, you should use:

  • Unpaywall, built by Impactstory, is a database of full text open access articles, harvested from repositories and publishers.


There are a few apps which help you identify Open Access articles.

  • Unpaywall Extension – Based on the Unpaywall database, their browser extension will use the information on a web page to link you to an open version of an article is freely available.
  • Open Access Button – Once you know about an article, you can enter the title or DOI into the website and determine if an Open Access version is available. There’s also a Firefox extension you can use while you’re searching.

Innovation and research around Open Access, Open Data, and Open Science is ongoing, so more tools will become available with time. Check back with the library to learn more about the always-changing world of scholarly publishing.