An article is open access if it is accessible without a paywall. It could be open access on the publisher's website, in an open access repository (e.g., ScholarSphere, PubMed Central, or NSF-PAR), or elsewhere on the web.

It can be difficult to check open access status when you are on a Penn State network. Even if you do not access the article through the Libraries website or log in to a Libraries database, you may be getting access to the article because of a Penn State subscription. In other words, you are already past the paywall.

Tools for checking access

Open Access Button is an excellent tool for checking the open access status of journal articles. On that website, enter the article's title or DOI to check if it is freely available. This will find open access copies on publishers' sites and in repositories.

Unpaywall is another great source for this information. If you have many articles to check, use Unpaywall's Simple Query Tool to enter a list of DOIs and get results from its API. You can also query the Unpaywall and Open Access Button APIs directly (see Analyzing Institutional Publishing Output: A Short Course to learn more).

Both tools also offer browser extensions so you can check access while browsing the internet. Since these tools are designed to get access to the articles rather than check access status, we don't recommend them for this work. If you are already past a paywall, the browser extensions will often indicate that the article is open access, even though it is not.

Another shortcoming of Open Access Button and Unpaywall is that they don't include every article ever published. The article you want to check may not be in either database, especially if it does not have a DOI.

Checking access on the publisher's website

Sometimes you may want to check access directly on the publisher's website. To check for a paywall on the publisher's website, use a device that is not authenticated to any Penn State accounts (a private browser window can work well for this) and connect to the Internet from a non-Penn State network. (This means you should not use the VPN either.)

Another thing to check for is a Creative Commons license on the copy of the article on the publisher's website. This will generally mean that the article is not behind a paywall either.

Checking access in PubMed and PubMed Central

PubMed and PubMed Central are both maintained by the National Library of Medicine (NLM) within the National Institutes of Health (NIH). Per NLM, "The PubMed database contains more than 37 million citations and abstracts of biomedical literature. It does not include full text journal articles; however, links to the full text are often present when available from other sources, such as the publisher's website or PubMed Central (PMC)."

The article's PubMed record is often a top search result for the article's title. In that record, look for the "PMCID." If there is a PMCID, that means the article has been deposited in PubMed Central. It may be under a short embargo, but it will be publicly available soon. If there is no PMCID, it is not available.

If the article is in PubMed Central, even under an embargo, this satisfies Penn State's open access policy, and you don't need to do anything further.