Table 1. Number of Records on Preprint Servers on May 29, 2020a.
| Server name | No. of recordsb |
|---|---|
| arXiv | 1 708 255 |
| Social Science Research Network (SSRN)c | 802 602 |
| EconStor (economics and business studies) | 119 864 |
| bioRxivc | 84 009 |
| RePEc/Munich Personal RePEc Archive | 49 164 |
| PhilArchive | 48 927 |
| Hyper Articles en Ligne (HAL) | 48 610 |
| ViXra | 35 827 |
| OSF Preprintsc | 17 174 |
| INA-Rxivc | 16 641 |
| Cryptology ePrint Archive | 14 817 |
| Preprints.orgc | 14 052 |
| ChinaXivc | 13 682 |
| Research Squarec,d | 12 962 |
| Mathematical Physics Preprint Archive | 9601 |
| PsyArXivc | 9475 |
| Social Science Open Access Repository (SSOAR) | 8193 |
| JMIR Preprintsc | 7888 |
| Optimization Online | 7531 |
| medRxivc | 5935 |
| SocArXiv | 5497 |
| LingBuzz | 5113 |
Servers not listed above include the following 12 servers with greater than 500 and less than 5000 records: ChemRxiv, Authorea Preprint Repository, PhilSci-Archive, Electronic Colloquium on Computational Complexity, Zenodo, EarthArXiv, LawArXiv, engrXiv, Thesis Commons, e-LIS, Earth and Space Science Open Archive (ESSOAr), and Advance (SAGEpub). Also not listed above are the following 23 servers with less than 500 records: EdArXiv, Commons Open Repository Exchange (CORE)/Humanities Commons, MarXiv, Arabixiv, AgriXiv, LIS Scholarship Archive (LISSA), EcoEvoRxiv, SportRxiv, MindRxiv, APSA Preprints, PaleorXiv, MetaArXiv, AfricArXiv, ECSarXiv, IndiaRxiv, FrenXiv, MediArXiv, NutriXiv, BodoArXiv, OARR: Open Anthropology Research Repository, FocUS Archive, MitoFit Preprint Archives, and BioHackrXiv.
The term records is intentional, as not all servers have filters that clearly differentiate between preprints and published articles or account for duplicate records.
These servers allowed health sciences discipline selection during the submission process.
For Research Square, only preprints not undergoing journal peer review were included.