Content last reviewed:
- American Chemical Society (ACS) - Emphasis on chemistry, materials science, and chemical engineering - a combination of fully (Gold OA) and partially (Hybrid) OA journals + ACS Journal Finder
- Biomed Central (BMC) - Primarily science and engineering, part of Springer Nature
- CORE - Attempts to aggregate all open access research outputs from repositories and journals worldwide
- DOAJ (Directory of Open Access Journals) - Search international, peer-reviewed Journals
- Frontiers - Focus on the sciences
- MDPI - Open scientific exchange across all disciplines serving scholars from around the world
- Paperity - Multi-disciplinary and multi-lingual aggregator of OA journals and papers
- PeerJ - Medical, Biology, Computer Science, Chemistry, Materials Science
- PLOS (Public Library of Science) - Research focused on medicine and science
- PubMed Central (PMC) - Biomedical and Life Sciences
- RePEc - (Research Papers in Economics) Working papers, journal articles, books, chapters, and software components
- Semantic Scholar - Search for academic publications using machine learning techniques from PubMed, Nature, ArXiv, and more
- SSRN (Social Science Research Network) - Search or browse abstracts and/or full-text, including conference proceedings
Unpaywall browser extension
- Install this in your browser for when you encounter an inaccessible commercial journal article -- it will automatically search for OA versions (including pre-prints) from Unpaywall's index of repositories
Assessing Legitimacy
- You may wish to review Beall's List of Predatory Journals and Publishers, a list of questionable scholarly open-access content
- And consider a quick search in the Retraction Watch Database for articles retracted since publication
- agriRxiv - Preprints for Agriculture and Allied Sciences
- arXiv.org* - Focus on Physics, Mathematics, Computer Science, Quantitative Biology, Quantitative Finance, and Statistics
- bioRxiv* - Preprint server for Biology
- ChemRxiv* - Preprint server for Chemistry
- Earth ArXiv - Preprint service for the Earth sciences
- eLife - Reviewed Life Sciences and Medicine PrePrints
- engrXiv - Engineering Archive of preprints and previously published articles made openly accessible
- ESSOAr - Earth and Space Science Open Archive
- f1000Research - Portal to discipline-focused preprint communities
- medRxiv* - The preprint server for health sciences
- OSF Preprints - Portal to discipline-focused preprint communities
- Preprints* - Multidisciplinary Preprint Platform
- PsyArXiv - For the Psychological Sciences
- Research Square - Multidisciplinary Preprint Platform
- TechRxiv - Preprints in Technology Research
- viXra.org - Alternative to arXiv.org
- zenodo - Repository for research data and preprints
*can cross-search these repositories via Web of Science [on landing page, change "Search in" from "All Databases" to "Preprint Citation Index"]
PrePrint Reviews
- DOAB (Directory of Open Access Books) - Peer-reviewed books from international academic publishers
- FreeTechBooks - Computer Science, Engineering, and Programming
- IntechOpen - Peer-reviewed OA books in STEM
- LibriVox - Audio recordings of public domain books
- The National Academies Press - Published reports from the National Academies of Sciences, Engineering and Medicine (U.S.)
- OAPEN (Open Access Publishing in European Networks) - Open access, peer-reviewed books
- The Online Books Page - Searchable indices by author, title, or subject
- Open Library - Classic literature, including books in accessible formats
- Open Research Library (ORL) - comprehensive, multidisciplinary collection of peer-reviewed OA books
- Project Gutenberg - Books on a variety of subjects, in multiple languages
- Standard Ebooks - Free public domain ebooks which are open source and accessible
- Applied Math and Science Education Repository (AMSER) - STEM resources
- AtlanticOER Pressbooks Network - Founded by the Council of Atlantic University Libraries (CAUL-CBUA)
- BCcampus: OpenEd - B.C. Open Textbook Collection
- eCampusOntario - Open Library
- George Mason OER Metafinder - Real-time simultaneous search of OER sources
- LibreTexts - With embedded multimedia, dynamic figures, annotation overlay, and more
- Open ED Manitoba - Manitoba's Open Textbooks
- OpenStax Textbooks - Peer-reviewed, openly licensed
- Open Textbook Library - Peer-reviewed, openly-licensed textbooks
- Open Textbooks for Engineering - Assembled by the Engineering Libraries Division of ASEE
- Wikibooks - Open textbooks where anyone can edit the content
- AfricArXiv - Digital archive for African research, working towards building an African-owned open scholarly repository
- Archive-It! - Website archiving services (from the Internet Archive) focused on research institutions, libraries, and preserving cultural memory
- BASE (Bielefeld Academic Search Engine) - Academic content from around the world in a variety of formats
- CiteSeerX - Search engine for computer and information science literature freely available on the web
- Dimensions - Articles, chapters, preprints, and datasets linked through a single platform including publication metrics and altmetrics
- Dryad - Curates freely reusable data underlying scientific publications
- Europe PMC - Life-Sciences literature, including research articles, reviews, and preprints
- figshare - Multidisciplinary repository for various formats of research output
- Google Scholar - Index of scholarly literature with citation metrics
- Hathi Trust - Repository for digitized content from libraries and other research institutions around the world
- Internet Archive - Variety of digital content, including books, audio, video, software
- Internet Archive - Scholar - Research articles and other scholarly documents
- Lens.org - Linking the world's patents to scholarly, technical, regulatory, and business data and literature
- NASA Scientific and Technical Information Program - Scientific and technical aerospace research
- OAIster - Embedded into WorldCat, provides access to resources in open-archive collections
- Or search WorldCat and then tick "Open Access" at the top left of the results screen
- OASIS - Search engine for multiple open content sources
- OpenAIRE - Open dataset of publications, data, software, grants, and organizations
- Open DOAR (The Directory of Open Access Repositories) - Offers the ability to search for repositories by subject, country, language, type, or actually search the content of all indexed repositories
- Open Library of Humanities (OLH) - Hosted academic journals in the humanities
- OSTI.GOV - U.S. Department of Energy
- PhilPapers - Index of research content in philosophy from journals, books, archives, and researcher homepages
- Registry of Open Access Repositories - Search by country and repository type
- ResearchHub - Uploaded research articles organized by themed hubs as opposed to journals with ability to leave comments
- SciELO - Scientific literature produced in Latin America
- Scilit - Database of scholarly works used to collate data and index scientific material, maintained by MDPI and crawls CrossRef and PubMed daily
- SCOAP3 (Sponsoring Consortium for Open Access Publishing in Particle Physics) - Partnership of libraries, funding agencies, and research centres around the world -- focused on high-energy physics
- Carleton University's collection of Theses and Dissertations
- EBSCO Open Dissertations - linking institutional repositories worldwide
- EThOS - Theses and dissertations from the UK
- NDLTD (Networked Digital Library of Theses and Dissertations) - International theses and dissertations--or target regional repositories here
- OATD (Open Access Theses and Dissertations) - International theses and dissertations
- ProQuest - Full-text theses and dissertations
- Theses Canada (Library and Archives Canada) - Search Canadian theses and dissertations, including those with electronic access
- Borealis, the Canadian Dataverse Repository - Research data platform and repository for sharing, discovering, and preserving research data -- offered to Carleton faculty and scholars
- Carleton University Institutional Repository - Open access and other scholarly publications from Carleton University
- Digital Commons Network - Scholarly articles and other academic content from institutions around the world
- Institutional Repositories in Canada - from CARL, the Canadian Association of Research Libraries
- Coursera - Combination of free and paid-for courses
- edX - Online courses from top institutions
- Future Learn - Combination of free and paid-for courses, including microcredentials
- Khan Academy - Instructional videos and practice exercises
- Massachusetts Institute of Technology: MIT OpenCourseWare - MIT course content
- World Lecture Project (wlp) - Scholarly videos