Is MDPI Peer Reviewed or Predatory?

Yes — MDPI journals use peer review, and MDPI is not on predatory-publisher lists like Beall’s List. Still, MDPI’s fast review timelines and heavy reliance on guest-edited Special Issues have drawn documented scrutiny, including a 2023 Web of Science delisting and Norway’s 2021 downgrade of its publication-indicator ranking.

Predatory-Journal Checklist, Checked Against MDPI

Before the history below, here is the direct check: run MDPI against the markers CASRAI’s predatory journal definition actually uses, one at a time.

Common predatory-journal warning sign	Does MDPI show it?	What’s documented
No genuine peer review behind a publication fee	No	Single-blind review by external reviewers, with an academic editor (not MDPI staff) making the final accept/revise/reject decision, per MDPI’s stated policy.
No verifiable, named editorial board	No	Journals list named academic editors and editorial board members.
Currently on Beall’s List or a comparable predatory-publisher reference list	No	Added to Beall’s List in February 2014; formally appealed, and removed in October 2015 after an OASPA review found MDPI met membership criteria. Not on Beall’s List or comparable lists since.
No membership in publishing-standards bodies	No	Member of both COPE and OASPA, each of which involves a compliance review as a condition of membership.
Not indexed in any recognized database	No, for the great majority of titles	Indexed in Scopus and, where subject-relevant, PubMed; most journals remain in Web of Science after a 2023 review affected two of MDPI’s several hundred titles.
Zero independent scrutiny or criticism on record	This one is true — but it doesn’t mean predatory	Norway’s 2021 publication-indicator downgrade and the 2023 Web of Science delisting of two journals are real and documented. Both are quality/indexing decisions, not findings that peer review didn’t happen.

None of the six classic warning signs are present for MDPI as a publisher — which is why the definitional answer stays no, even though the specific, documented criticism later in this guide is real and worth reading before deciding how much scrutiny to apply to an individual MDPI article.

What MDPI Is

MDPI is a fully open-access academic publisher headquartered in Basel, Switzerland, founded in 1996. It publishes several hundred peer-reviewed journals spanning most academic disciplines, funded through article processing charges (APCs) rather than reader subscriptions — the same business model used by other large open-access publishers such as Frontiers, Hindawi, and the fully-OA portions of larger publishers’ portfolios. MDPI is a member of the Committee on Publication Ethics (COPE) and the Open Access Scholarly Publishers Association (OASPA), both of which set conduct and membership standards for scholarly publishers.

How MDPI’s Peer Review Process Works

MDPI states that its journals use single-blind peer review by default: a reviewer’s identity is withheld from the author, while the author’s identity is visible to the reviewer. Manuscripts are evaluated by independent external reviewers — MDPI’s stated policy requires a minimum number of reviewer reports before a decision is made — and the final accept, revise, or reject decision is made by an academic editor (an external researcher serving in that role for the journal), not by MDPI in-house staff. This is the same basic structure most peer-reviewed journals use: independent reviewers plus an editorial decision-maker with authority to overrule reviewer recommendations. For the general vocabulary this page draws on — what “single-anonymized” review actually means, how it differs from double-anonymized or open review — see CASRAI’s single-anonymized peer review entry and the ANSI/NISO Z39.106-2023 peer review terminology standard that formalized these terms.

The Legitimate Criticism, and What’s Actually Documented

Several distinct episodes get conflated in casual claims about MDPI. Treated separately, with what’s actually documented for each:

Beall’s List (2014–2015)

MDPI was added to Jeffrey Beall’s list of potentially predatory open-access publishers in February 2014, with Beall citing concerns about manuscript-solicitation practices and editorial-board listings. MDPI formally appealed. In October 2015, Beall’s own appeals board removed MDPI from the list, and a separate OASPA review concluded MDPI met OASPA’s membership criteria. MDPI has not been on Beall’s list (or its direct continuation) since.

Norway’s Publication Indicator (2021)

Norway’s national research-assessment body maintains a register (the Norwegian Scientific Index / Publication Indicator) that classifies journals by scholarly level for funding-allocation purposes, including a non-counting “Level X” category for titles with quality concerns. A number of MDPI journals were placed in or affected by this category in 2021, part of a broader set of concerns Norwegian assessors raised about rapid special-issue-driven journal growth. This is a national indexing/funding-classification decision, not a predatory-publisher designation.

Web of Science delisting (2023)

In March 2023, Clarivate (which operates Web of Science) discontinued coverage of two MDPI journals — the International Journal of Environmental Research and Public Health (IJERPH) and the Journal of Risk and Financial Management (JRFM) — citing the “Content Relevance” criterion in its journal evaluation process, notably not a finding about the quality of individual published articles. This was part of a larger Clarivate review that also delisted numerous journals from other publishers, including 19 Hindawi titles, after identifying several hundred journals of concern. MDPI publicly confirmed the IJERPH and JRFM decisions and formally appealed the IJERPH discontinuation. The great majority of MDPI’s several hundred journals remained indexed in Web of Science throughout.

Special Issues and review speed

MDPI’s growth strategy relies heavily on guest-edited Special Issues, and its stated review timelines are faster than many traditional subscription journals. Both practices are legal and disclosed, and MDPI states its Special Issue editorial standards match its regular-issue standards. They are also the recurring focus of independent commentary (including from industry publications like the Scholarly Kitchen) questioning whether review at that volume and speed can be applied as consistently as at smaller-scale, slower-turnaround journals. This is a fair question to weigh when choosing where to publish or how much scrutiny to apply to a specific MDPI article — it is a question about editorial rigor at scale, not a claim that review doesn’t occur.

Is MDPI a Predatory Publisher?

By the definitions used across the field — see CASRAI’s predatory journal entry — a predatory journal is characterized by the absence of genuine peer review behind a publication-fee business model, typically combined with deceptive practices about editorial board membership, indexing claims, or fees. MDPI does not meet that definition on the current record: it is not on Beall’s list (from which it was formally removed after appeal), it is not commonly included on other major predatory-publisher reference lists, and it maintains OASPA and COPE membership, both of which involve compliance review. The documented criticism above — a national indexing body’s quality classification, a Web of Science index-relevance delisting affecting two of several hundred titles, and ongoing debate about special-issue volume and review speed — is a case for informed scrutiny of specific journals or articles, not evidence that MDPI operates without peer review.

How to Verify Peer Review Status for Any Journal

The MDPI-specific facts above answer this one publisher’s case, but the more durable skill is knowing how to check any journal yourself, since the same question comes up for publishers with far less documentation available than MDPI. CASRAI’s How to Know If an Article Is Peer Reviewed guide walks through the concrete checks: journal website disclosure of review policy, indexing in recognized databases, editorial board verifiability, and publisher membership in COPE/OASPA/DOAJ. If you’re evaluating a journal you’re less sure about than MDPI, also see CASRAI’s guide to identifying predatory journals and publishers, which covers the warning signs that distinguish a genuinely predatory operation from a legitimate publisher that simply draws criticism.

Frequently Asked Questions

Is MDPI predatory?

No. By the definition CASRAI and the wider field use — genuine peer review absent behind a publication-fee model, typically paired with a fake or unverifiable editorial board — MDPI doesn’t meet it: peer review is documented and disclosed, editorial boards are named, and MDPI isn’t on Beall’s List or comparable predatory-publisher reference lists. Real, documented criticism does exist (Norway’s 2021 indicator downgrade, the 2023 Web of Science delisting of two journals, and debate over Special Issue volume and review speed) — but that’s a separate question from whether MDPI is predatory.

Is MDPI a legitimate publisher?

Yes, by the standard markers used to assess publisher legitimacy: it operates disclosed peer review, is a COPE and OASPA member, and is not on Beall’s list or comparable predatory-publisher references. It is also a publisher that draws real, documented criticism over review speed and special-issue volume — both facts can be true together.

Was MDPI ever classified as predatory?

It was added to Jeffrey Beall’s list in February 2014 and removed in October 2015 after a formal appeal and an OASPA review found it met membership criteria. It has not been added back since.

Why were some MDPI journals removed from Web of Science?

In March 2023, Clarivate discontinued Web of Science coverage of two MDPI journals (IJERPH and JRFM) citing its “Content Relevance” evaluation criterion, as part of a larger review that also delisted journals from other publishers. This affected two titles out of MDPI’s several hundred journals.

Is MDPI’s peer review too fast to be rigorous?

MDPI’s stated review timelines are faster than many traditional journals, which is part of both its appeal to authors and the basis for outside criticism about whether review at that speed and volume is applied consistently. There is no independent, verifiable industry-wide benchmark establishing a specific MDPI turnaround figure as fact, so treat specific day-count claims you see elsewhere with the same caution you’d apply to any single publisher’s self-reported metric.

Are MDPI journals indexed in major databases?

Most MDPI journals are indexed in databases such as Scopus and, where subject-relevant, PubMed, and the majority remain indexed in Web of Science following the 2023 review described above. Indexing status varies by individual journal and can change, so check the specific journal directly rather than assuming publisher-wide status.

Related CASRAI Resources

MDPI’s largest titles are the ones most often checked this way; see the IJMS impact factor entry.