What are Preprints?
Preprints are early versions of academic research (usually articles) made available online for free before peer-review, journal copy-editing or publication.
Advantages of Preprints
The formal article publishing process can be lengthy, taking many months from submission, peer-review to publication. Preprints allow you to share the results of your research much more quickly.
Preprints allow the subject community to read and evaluate the work, give you feedback and help you improve your work. Posting preprints in this way can be a useful method of improving your professional networks, allowing others to build on your work and opening possibilities for collaboration.
Most preprints are given a digital object identifier (DOI) so they can be cited in other research papers. The DOI also provides a “public timestamp” that establishes the primacy of your work.
Limits of Preprints
Although most publishers allow you to post preprints, some may have restrictions or even reject manuscripts that have been posted on preprint servers. It is important to check the policies of any journal you may wish to submit to before releasing a preprint. The Sherpa Romeo and the Transpose database make it easy to find the preprinting policies of journals.
As authors may post later versions of their articles as preprints again, there can be multiple versions of the same paper, making it difficult to identify the current version.
Readers of preprints must be mindful of the fact research posted on preprint servers has not undergone peer review. Mistaking preprints for peer-reviewed, published articles can lead to the spread of misinformation as we witnessed during Covid.
Leading Preprint Servers
Please note that this is just a selection and not a comprehensive list of preprint servers. You can find a more comprehensive list on https://asapbio.org/preprint-servers .
- arXiv: Launched in 1991 by Cornell University, this is the world's first preprint server. ArXiv hosts fields of computer science, maths, physics, and statistics. Indexed by Europe PMC, Google Scholar, and others.
- bioRxiv: A free preprint server for the life sciences. Indexed by Google Scholar, Microsoft Academic, Meta, Europe PMC, SHARE, Crossref, and PubMed (NIH-supported COVID preprints only).
- ChemRxiv: Subject specific server that hosts unpublished preprints in chemistry, including biological and medicinal chemistry. This is another nonprofit server launched in 2017 by a consortium of academic societies in chemistry. It is indexed by Google Scholar, Europe PMC, Chemical Abstracts Services, Crossref, PubMed (NIH-supported COVID preprints only), ProQuest, Scopus.
- medRxiv: A preprint server for research in the medical, health sciences, and clinical fields. Indexed by Google Scholar, Microsoft Academic Search, Crossref, Europe PMC, PubMed (NIH-supported COVID preprints only).
- MetaArXiv: A multidisciplinary archive of articles owned by The Berkeley Initiative for Transparency in the Social Sciences. Indexed by Google Scholar, SHARE, Microsoft Academic, Unpaywall.
- Preprints.org: This server was launched in 2020 by the Multidisciplinary Digital Publishing Institute (MDPI). As the name of the organization implies, this nonprofit server accepts manuscripts from all fields of research and makes this research immediately available after submission. Indexed by Google Scholar, PrePubMed, Europe PMC, SHARE, SciLit.
- OSF Preprints: Supported by the Centre for Open Science, OSF is a free and open platform that supports a variety of discipline-specific preprint servers. The OSF search aggregator allows users to search through its own preprint collections and those of other organizations. Indexed by Google Scholar, SHARE, Microsoft Academic, Unpaywall
- Zenodo: A general-purpose open repository for all subjects developed under the European OpenAIRE program and operated by CERN. Indexed by Google Scholar, SHARE, Microsoft Academic, Unpaywall, OpenAIRE, DCI, Mendeley Data, Figshare.
Useful Links
Read our blog post on Embracing Preprints: Why Sharing Your Research Early Matters
View the recording and slides of our ExplORe: Open Research Essentials session on Preprints