You can usually tell if an article is peer reviewed by checking a few specific places: the journal’s website, the article itself, or the database where you found it. Most library databases let you filter results to show only peer-reviewed content, which is the fastest method. But when that’s not an option, there are reliable manual checks that take just a few minutes.
Use Database Filters First
If you’re searching through a university library database like Academic Search Complete or other EBSCO-powered tools, look for a checkbox labeled “Peer Reviewed” or “Scholarly (Peer Reviewed)” near the search box or in the left sidebar of your results page. Check that box before or after you search, and the database will only show articles from journals with a confirmed peer-review process. This is the single most reliable shortcut available to you.
PubMed, the massive biomedical database run by the National Library of Medicine, works a bit differently. It doesn’t have a dedicated “peer reviewed” checkbox, but you can use the MEDLINE filter (by clicking it in the sidebar or adding medline[sb] to your search). Articles indexed for MEDLINE come from journals that have passed a rigorous selection process, which includes evaluation of their review practices. This isn’t identical to a peer-review filter, but it narrows your results to well-vetted journals.
Google Scholar is a common starting point for research, but it has no peer-review filter at all. If you find an article there, you’ll need to verify the journal’s review status yourself using the methods below.
Check the Journal’s Website
Every reputable journal states its review process on its own site. Look for sections labeled “About the Journal,” “Editorial and Journal Policies,” “Peer Review Process,” or “Instructions for Authors.” These are typically found in the main navigation menu or in a dedicated author center. PNAS, for example, lists its peer review process under an “Author Center” menu that includes separate pages for editorial policies and the review process itself. Most journals follow a similar structure.
What you’re looking for is a clear statement that submitted manuscripts are evaluated by independent experts before publication. If the journal doesn’t mention peer review anywhere on its site, or if the description is vague, that’s a red flag.
Look for Dates Inside the Article
Peer-reviewed articles almost always display a set of dates near the top or bottom of the first page, or in the article’s metadata online. The key dates to look for are “Received,” “Revised,” and “Accepted.” A typical sequence might read: Received March 5, 2023; Revised June 12, 2023; Accepted July 1, 2023.
That gap between “Received” and “Revised” tells you something important. It means reviewers read the manuscript, requested changes, and the authors went back and reworked it. If a major revision was recommended, the revised version goes back to the original reviewers for a second round of evaluation. If only minor revisions were needed, an editor may assess the changes directly and accept the paper. Either way, those dates are a concrete footprint of the review process. An article that shows only a submission date and a publication date, with no revision step, likely did not go through formal peer review.
Use Ulrich’s Periodicals Directory
If you want to verify a specific journal’s status, Ulrich’s Periodicals Directory (often called Ulrichsweb) is the standard reference tool. Many university libraries provide access. Search for the journal title, and look for a small icon shaped like a referee’s jersey next to the listing. That icon indicates the journal is refereed, which is another word for peer reviewed. Ulrich’s is cautious: they don’t display that icon until they’ve confirmed the journal’s review practices.
For open-access journals specifically, the Directory of Open Access Journals (DOAJ) is another verification tool. DOAJ reviews applications from journals seeking inclusion and investigates signs of poor peer-review processes. Journals listed in DOAJ have met criteria for editorial oversight, including peer review handled by qualified reviewers. If a journal claims to be peer reviewed but isn’t listed in either Ulrich’s or DOAJ, it’s worth investigating further.
Not Everything in a Peer-Reviewed Journal Is Peer Reviewed
This trips up a lot of people. A journal can be peer reviewed, but that doesn’t mean every piece of content in it went through the review process. Editorials, letters to the editor, book reviews, commentaries, and opinion pieces are commonly published alongside peer-reviewed research articles in the same issue. These shorter pieces are typically invited or approved by editors, but they aren’t sent out to independent reviewers for evaluation. If your professor or assignment requires peer-reviewed sources, make sure the specific item you’re citing is a research article or review article, not one of these other content types.
How Peer Review Actually Works
Understanding what peer review looks like can help you spot it. After an author submits a manuscript, the journal’s editor sends it to two or more independent experts in the same field. Those reviewers evaluate the methods, data, reasoning, and conclusions, then recommend whether the paper should be accepted, revised, or rejected.
Most journals use some form of blinded review. The most common model is single-blind, where the reviewers know who wrote the paper but the authors don’t know who reviewed it. Double-blind review hides identities in both directions, and this is the format used by most medical journals. Triple-blind review goes further by also keeping the handling editor anonymous. Some journals use open peer review, where authors and reviewers know each other’s identities, and the reviewers’ comments are sometimes published alongside the final article.
None of these models is inherently better for the reader trying to verify quality. What matters is that independent evaluation happened at all.
Red Flags for Fake Peer Review
Some journals claim to be peer reviewed but aren’t, or their review process is so superficial it’s meaningless. These are often called predatory journals, and they make money by charging authors publication fees while providing little or no real editorial oversight.
Watch for these warning signs:
- Unrealistically fast turnaround. Legitimate peer review takes weeks to months. If a journal promises acceptance in days, the review is likely nonexistent.
- No description of the review process. Credible journals explain their process openly. A missing or vague description is a concern.
- Aggressive solicitation emails. If you or your professor received an unsolicited email begging for submissions, especially with flattering language and tight deadlines, be skeptical.
- Missing from major indexes. If the journal doesn’t appear in PubMed, Ulrich’s, DOAJ, or well-known discipline-specific databases, it may not meet quality standards.
When in doubt, cross-check the journal against multiple sources. A journal that appears in Ulrich’s with the refereed icon, is indexed in major databases, and displays clear submission-to-acceptance timelines on its published articles is almost certainly running a genuine peer-review process.