No, you don’t have to pay to read this blog post. Or most scientific articles.

I often blog about peer-reviewed articles, and some of those articles are behind a paywall. There’s a large and growing trend toward open access journals, which charge the authors a publication fee and make their articles available to everyone for free, but this is far from universal. A lot of the big, high-profile journals, such as Science, Nature, PNAS, Ecology Letters, and Current Biology still charge for their articles. And the charges aren’t trivial. A typical scientific paper might cite 50-100 previous articles, and an author might have to read two or three times that many that don’t end up being cited. If you had to pay $38 for each one of those articles, you’d be a lot less inclined to do a thorough literature search.

This isn’t usually a problem for those of us who work on university campuses, because we have institutional subscriptions to the journals. This means that when we’re on campus using the university’s ethernet, we don’t even see the paywall, just go straight to the article. Even when we’re off campus, we can get the articles just by using our institution’s VPN.

But what if you don’t work for a university and you still want to read an original, peer-reviewed article? There are good reasons to do so. If you never do, you have to rely on secondary sources: news articles about the research, blogs like this one, and the like. So all you ever hear is the news outlets’ interpretation of the research, which may or may not accurately reflect what the research actually says. Furthermore, those news outlets will rarely question whether the claims of the research are true! If you want to see what the researchers did and evaluate their evidence for yourself, you have to read the original paper.

And you almost always can, without paying anything. Here’s how. First, the article may be open access. If it’s in one of the PLoS (Public Library of Science) or BMC (BioMed Central) journals, it is. For example, if you want more detail than I gave about Nozaki and colleagues discovery of a new Volvox species, anyone can access the PLoS One article. BioRxiv articles (which are not peer reviewed, but sometimes show up in news articles and blog posts) are always open access. If you want to judge Betül Kaçar’s latest research for yourself, you can.

Even if it’s not a fully open-access journal, the article itself may be open access. Many traditional, subscription-based journals offer authors the option to pay a fee to make their article open access. So if you want to read about experimental evolution in Molecular Ecology, you can.

Email the corresponding author.

Even if the article is behind a paywall, though, you still have options. Try a Google Scholar search. If the first hit doesn’t lead you to a pdf, try clicking the “All [x] versions” link; one of them may. Or try a regular search for the authors’ websites. We’re a vain lot, and most of the time our websites will include links to our papers. If all else fails, you can always email the corresponding author. Their address will be on the journal’s website (on the page you can’t get past without paying). They will almost always be happy to send you a pdf of their article. If they don’t, they’re probably retired, dead, or just a jerk, and the first two problems rarely come up for recent articles.