Compare
PREreview vs Unjournal
PREreview is a free, open-source platform where researchers write and publish open reviews of preprints, often as a community; Unjournal recruits reviewers matched to a paper at the author's request, runs a double-blind review and a revision round, and lets the author publish the endorsed version. PREreview reviews a preprint; Unjournal turns a paper into a peer-reviewed preprint.
How PREreview works
PREreview's mission is to bring more openness and equity to peer review by helping any researcher review preprints. Reviewers sign in with an ORCID iD and can publish under their name or under an assigned pseudonym. Reviews are public and archived in PREreview's Zenodo Community.
Authors can request reviews of their preprint, and the community can answer. PREreview also runs collaborative formats (Live Reviews, PREreview Clubs) and training and mentorship in constructive peer review. It does not make accept or reject decisions or publish papers.
How Unjournal works
- You upload your paper (PDF or Word). It is read for the specific questions that need an expert, and nothing is sent to anyone yet.
- Researchers whose own work is closest to those questions are found in the global publication record, and you approve the anonymized shortlist.
- They review it double-blind, commenting on the passages that matter.
- You revise, and the same reviewers check the revision against their comments.
- Once at least two endorse it and none says “not yet”, you can publish it on the Unjournal preprint journal with its reviews. You keep the copyright.
Uploading and seeing the shortlist are free, publishing is free, and the review is paid once it is delivered, with a money-back guarantee.
The real differences
Who reviews. On PREreview, whoever chooses to answer a request or pick up a preprint reviews it. On Unjournal, reviewers are selected for the paper's specific questions from the publication record and the author approves them.
Revision. A PREreview is a review of a given version. On Unjournal the same reviewers check the revision and endorse it.
What you end up with. PREreview leaves your preprint where it is, with public reviews attached. Unjournal publishes the endorsed revision as a peer-reviewed preprint with its reviews.
Cost. PREreview is free. Unjournal's review is paid on delivery.
| Criterion | PREreview | Unjournal |
|---|---|---|
| Who reviews | Researchers who choose to, individually or in clubs | Matched to the paper's questions; the author approves an anonymized shortlist |
| Reviewer identities | Named, or under a PREreview pseudonym | Double-blind: reviewers and author are anonymous to each other |
| Reviews public | Yes, archived in its Zenodo Community | Yes, published alongside the paper |
| Revision checked by the reviewers | Not part of the process | Yes, by the same reviewers |
| What the paper becomes | Your preprint, with public reviews | A peer-reviewed preprint on the Unjournal preprint journal |
| Cost to the author | Free | Free to upload and publish; the review is paid on delivery, with a money-back guarantee |
When PREreview is the better fit
If you want open, community feedback on a preprint at no cost, or you want to learn to review and take part in review clubs, PREreview is built for that. Unjournal fits better if you need reviewers chosen for your paper's specific questions, a double-blind review with a revision round, and a reviewed version you can publish.
Frequently asked questions
Is PREreview free?
Yes. PREreview describes itself as a free, open-source review platform.
Can I request reviews of my preprint on PREreview?
Yes. PREreview has a review request feature; reviewers from its community can then pick up the request.
Are PREreview reviewers anonymous?
Reviewers sign in with ORCID and can publish under their own name or under a PREreview pseudonym, chosen review by review.
Does Unjournal publish reviews openly?
Yes. When you publish your peer-reviewed preprint, its reviews appear alongside it. The reviewers stay anonymous.
Sources
- PREreview: About: mission, free open-source platform, Zenodo Community, Live Reviews, clubs, trainings (read 26 October 2026)
- PREreview: home: review requests (read 26 October 2026)
- PREreview: how to use the platform (French help page): ORCID sign-in and the pseudonym option (read 26 October 2026)