How to Find Research Papers for Free (and Get the Paywalled Ones Legally)
By Jessica McLaren 8 min read
To find research papers for free, search Google Scholar, CORE and open-access archives such as PubMed Central. When a paper sits behind a paywall, do not pay yet. Copy its DOI, search for it in your university library, look for the author’s own copy in a repository, ask for an interlibrary loan, or email the author.
Definition: open access. An open-access paper is free for anyone to read online. The Budapest Open Access Initiative defines open access as “free availability on the public internet”. A paywalled paper is one you can read only if you or your library has paid.
Where can I find research papers for free?
You can find free research papers in Google Scholar, in open-access collections and on preprint servers. Start with Google Scholar, then try the collection closest to your subject. To work out what counts as a proper source, see how to find academic sources. This guide starts where you need to read the paper.
| Where | What you get | Watch out for |
|---|---|---|
| Google Scholar | Every subject, with a [PDF] link beside a result when it finds a copy you can read | It lists paywalled papers too |
| CORE | Open-access papers gathered from repositories and journals | It also takes in preprint servers, so check whether a paper was published |
| DOAJ | An index of open-access journals from around the world | It covers open-access journals only |
| PubMed Central | A free full-text archive of biomedical and life sciences journal literature | Some papers appear only after an embargo, a delay before the full text is free |
| arXiv and bioRxiv | Preprints: arXiv in physics, maths, computer science, economics and related fields, bioRxiv in the life sciences | Not peer reviewed, so check whether you can cite a preprint |
| SciELO SA and AJOL | SciELO SA holds selected peer-reviewed South African journals, free to read. AJOL indexes journals published in Africa | Not all of AJOL is free: 461 of its 985 journals are open access |
How do I find free papers on my topic in one search?
To find free papers on your topic in one search, use a tool that checks the links for you, such as Litrevu’s free Research Paper Finder. Type your topic, with no sign-up, and it searches OpenAlex, “a comprehensive index of the world’s research”, for journal articles. It tests each open-access PDF link before listing it. For the papers it cannot fetch, it gives you the DOI, ready for the steps below. It never downloads a paywalled paper.
It does not find everything. It shows at most 15 papers in each list, and only journal articles that OpenAlex holds, so books and theses will not appear. A paper can land on the list of papers to get yourself even when it is free to read, because some publishers block automatic downloads, and it does not fetch papers that are free on the publisher’s page without an open licence.
For a thesis or a systematic review, also search your library’s databases and keep a record: how to write a search strategy shows you how. Then take your best paper and follow its citations to the papers a keyword search missed.
What is a DOI, and how do I use one?
A DOI is a permanent ID for a paper, and it is the most useful thing to copy when you hit a paywall. It looks like 10.1000/182, the example the DOI Foundation uses. Put https://doi.org/ in front of it and you have a link to the paper.
Look for the DOI near the title on the publisher’s page. If you only have a title, paste it into Crossref’s free metadata search. A DOI will not take you through a paywall: it often lands on the page with the abstract. What it gives you is an exact match, so your library finds this paper and not one with a similar title.
How do I get a paywalled paper legally?
Get a paywalled paper legally by working through these six steps in order. They start with what you can do alone and end with asking a person.
- Check the other versions. The same paper can sit in several places, so search its exact title in Google Scholar. Its help page says to “click a link labeled [PDF] to the right of the search result”, or to try “All versions” under it.
- Add a browser extension. It does the checking on every paper you open. Unpaywall looks for a free copy of the paper on your screen, and says it “points you to legal, author-posted manuscripts”. CORE Discovery is another free extension for the same job.
- Search your library with the DOI. Your library may already pay for that journal. Sign in to its search and paste the DOI or the title. Studying from home? Ask your library how to reach its journals off campus.
- Find the author’s repository copy. Many authors post a version of a paper in their university’s repository, so search their name and the title there. New papers may not be up yet: embargoes usually run 12 months in the sciences, and 18 months at Taylor & Francis or 24 at Wiley in the social sciences and humanities. The copy may be the accepted manuscript, which Elsevier says has no publisher copy-editing or pagination, so check page numbers before you quote.
- Ask for an interlibrary loan. Your library requests a copy from another library. Rules differ, as three South African libraries show. At Unisa, the service is free for staff and for registered master’s and doctoral students. At Wits, it is primarily for staff, researchers and postgraduates, and “there is usually a cost incurred”. At UCT’s Graduate School of Business library, “PDFs of e-journal articles will be e-mailed to you directly”. Undergraduates may not qualify, so ask.
- Email the author. This is normal. The University of Hull library says “It is common academic practice to request copies of journal articles direct from the author.” Look for the corresponding author’s address in the abstract. They may send the published version or a pre-print, “depending upon publisher restrictions”, or they may say no. Asking costs one email.
Steal this email. Copy it, fill in the brackets and keep it short:
Subject: Request for a copy of your paper on [topic]
Dear [title and surname],
I am a [level] student at [university], working on [topic]. Your [year] paper in [journal], “[title]” (DOI: [DOI]), looks directly relevant, but my library does not have access to it. Would you be willing to send me a copy for my own study?
Thank you for your time.
[Your name]
What do the open-access colours mean?
The open-access colours tell you why a paper is free and which copy you are reading. These definitions follow a 2018 study in PeerJ by Piwowar and colleagues.
| Colour | Where the free copy is | What it means for you |
|---|---|---|
| Gold | In an open-access journal | Free at the journal |
| Hybrid | In a subscription journal, under an open licence | Free at the journal, though its other papers may be paywalled |
| Green | In a repository, while the publisher’s copy is paywalled | Free, but it may be a version from before the final one |
| Bronze | On the publisher’s page, with no clear licence | Free to read today, and it may not stay free |
The same study estimated that “at least 28% of the scholarly literature is OA”, rising to 45% of articles from 2015, the newest year it covered. More than half of papers in biomedical research and mathematics were free, against less than 20% in chemistry and in engineering and technology. Those figures are years old, but the lesson holds: free copies will cover part of your list, and how much depends on your subject.
What do I do once I have the papers?
Once you have the papers, read them closely. Litrevu helps with that part.
Litrevu is an AI assistant for writing backed by sources. It reads every paper, report and PDF you add, answers your questions with a citation to the exact passage behind each claim, compares sources side by side, and checks your own draft against them.
Comparing papers side by side is also how you start to see what they leave open, which is the first step in finding a research gap. The reading, the judgement and your own writing stay yours.
Frequently asked questions
Is it legal to read free research papers online?
Yes, when the copy comes from a publisher, an open-access archive, a university repository or your library. Free to read is not the same as free to reuse: PubMed Central points out that free access “does not mean that there is no copyright protection”. Cite the paper as usual, and check the licence before you republish a figure.
Are free research papers lower quality than paid ones?
Not because they are free. Open access describes how a paper reaches you, not how good it is. Check it like any source: did it go through peer review, where was it published, and has it been retracted?
Can I get research papers if I am not at a university?
Yes. Google Scholar, CORE, PubMed Central, preprint servers, browser extensions and repositories are open to anyone, and anyone can email an author. Only the two university library steps need a student login.
What if I can only read the abstract?
Keep working through the paywall steps, and do not cite the paper yet: an abstract gives you the claim, not the method behind it. If you cannot get the paper, ask a librarian or your supervisor, or use a paper you can read that makes the same point. If you only know it through another author, cite it as a source within a source.
Does Litrevu download paywalled papers?
No. Litrevu only fetches open-access papers. For anything else, the Research Paper Finder gives you the DOI. Once you have the PDF, you can upload it to Litrevu with the rest of your papers.
What should you do next?
Type your topic into the free Research Paper Finder. Open the PDFs it finds, then take the DOIs of the rest through the six steps above. Find papers on your topic.