Online Journal and Research Databases
Navigating OA journals, research article databases, and academic websites trying to find high-quality sources for your research can really make your head spin. What constitutes a reliable database? What is a useful resource for your discipline and research topic? How can you find and access full-text, peer-reviewed articles?
Fortunately, we’re here to help. Having covered some of the ins and outs of peer review, OA journals, and how to search for articles, we have compiled a list of the top 21 free online journals and the best research databases. This list of databases is a great resource to help you navigate the wide world of academic research.
These databases provide a variety of free sources, from abstracts and citations to full-text, peer-reviewed OA journals. With databases covering specific areas of research and interdisciplinary databases that provide a variety of material, these are some of our favorite free databases, and they’re totally legit!
1. CORE
CORE is a multidisciplinary aggregator of OA research. CORE has the largest collection of OA articles available. It allows users to search more than 219 million OA articles. While most of these link to the full-text article on the original publisher’s site, or to a PDF available for download, five million records are hosted directly on CORE.
CORE’s mission statement is a simple and straightforward commitment to offering OA articles to anyone, anywhere in the world. They also host communities that are available for researchers to join and an ambassador community to enhance their services globally. In addition to a straightforward keyword search, CORE offers advanced search options to filter results by publication type, year, language, journal, repository, and author.
CORE’s user interface is easy to use and navigate. Search results can be sorted based on relevance or recency, and you can search for relevant content directly from the results screen.
Collection: 219,537,133 OA articles
Other Services: Additional services are available from CORE, with extras that are geared toward researchers, repositories, and businesses. There are tools for accessing raw data, including an API that provides direct access to data, datasets that are available for download, and FastSync for syncing data content from the CORE database.
CORE has a recommender plug-in that suggests relevant OA content in the database while conducting a search and a discovery feature that helps you discover OA versions of paywalled articles. Other features include tools for managing content, such as a dashboard for managing repository output and the Repository Edition service to enhance discoverability.
Good Source of Peer-Reviewed Articles: Yes
Advanced Search Options: Language, author, journal, publisher, repository, DOI, year
2. ScienceOpen
Functioning as a research and publishing network, ScienceOpen offers OA to more than 74 million articles in all areas of science. Although you do need to register to view the full text of articles, registration is free. The advanced search function is highly detailed, allowing you to find exactly the research you’re looking for.
The Berlin- and Boston-based company was founded in 2013 to “facilitate open and public communications between academics and to allow ideas to be judged on their merit, regardless of where they come from.” Search results can be exported for easy integration with reference management systems.
You can also bookmark articles for later research. There are extensive networking options, including your Science Open profile, a forum for interacting with other researchers, the ability to track your usage and citations, and an interactive bibliography. Users have the ability to review articles and provide their knowledge and insight within the community.
Collection: 74,560,631
Other Services: None
Good Source of Peer-Reviewed Articles: Yes
Advanced Search Options: Content type, source, author, journal, discipline
3. Directory of Open Access Journals
A multidisciplinary, community-curated directory, the Directory of Open Access Journals (DOAJ) gives researchers access to high-quality peer-reviewed journals. It has archived more than two million articles from 17,193 journals, allowing you to either browse by subject or search by keyword.
The site was launched in 2003 with the aim of increasing the visibility of OA scholarly journals online. Content on the site covers subjects from science, to law, to fine arts, and everything in between. DOAJ has a commitment to “increase the visibility, accessibility, reputation, usage and impact of quality, peer-reviewed, OA scholarly research journals globally, regardless of discipline, geography or language.”
Information about the journal is available with each search result. Abstracts are also available in a collapsible format directly from the search screen. The scholarly article website is somewhat simple, but it is easy to navigate. There are 16 principles of transparency and best practices in scholarly publishing that clearly outline DOAJ policies and standards.
Collection: 6,817,242
Other Services: None
Good Source of Peer-Reviewed Articles: Yes
Advanced Search Options: Subject, journal, year
4. Education Resources Information Center
The Education Resources Information Center (ERIC) of the Institution of Education Sciences allows you to search by topic for material related to the field of education. Links lead to other sites, where you may have to purchase the information, but you can search for full-text articles only. You can also search only peer-reviewed sources.
The service primarily indexes journals, gray literature (such as technical reports, white papers, and government documents), and books. All sources of material on ERIC go through a formal review process prior to being indexed. ERIC’s selection policy is available as a PDF on their website.
The ERIC website has an extensive FAQ section to address user questions. This includes categories like general questions, peer review, and ERIC content. There are also tips for advanced searches, as well as general guidance on the best way to search the database. ERIC is an excellent database for content specific to education.
Collection: 1,292,897
Other Services: None
Good Source of Peer-Reviewed Articles: Yes
Advanced Search Options: Boolean
5. arXiv e-Print Archive
The arXiv e-Print Archive is run by Cornell University Library and curated by volunteer moderators, and it now offers OA to more than one million e-prints.
There are advisory committees for all eight subjects available on the database. With a stated commitment to an “emphasis on openness, collaboration, and scholarship,” the arXiv e-Print Archive is an excellent STEM resource.
The interface is not as user-friendly as some of the other databases available, and the website hosts a blog to provide news and updates, but it is otherwise a straightforward math and science resource. There are simple and advanced search options, and, in addition to conducting searches for specific topics and articles, users can browse content by subject. The arXiv e-Print Archive clearly states that they do not peer review the e-prints in the database.
Collection: 1,983,891
Other Services: None
Good Source of Peer-Reviewed Articles: No
Advanced Search Options: Subject, date, title, author, abstract, DOI
6. Social Science Research Network
The Social Science Research Network (SSRN) is a collection of papers from the social sciences community. It is a highly interdisciplinary platform used to search for scholarly articles related to 67 social science topics. SSRN has a variety of research networks for the various topics available through the free scholarly database.
The site offers more than 700,000 abstracts and more than 600,000 full-text papers. There is not yet a specific option to search for only full-text articles, but, because most of the papers on the site are free access, it’s not often that you encounter a paywall. There is currently no option to search for only peer-reviewed articles.
You must become a member to use the services, but registration is free and enables you to interact with other scholars around the world. SSRN is “passionately committed to increasing inclusion, diversity and equity in scholarly research,” and they encourage and discuss the use of inclusive language in scholarship whenever possible.
Collection: 1,058,739 abstracts; 915,452 articles
Other Services: None
Good Source of Peer-Reviewed Articles: Yes
Advanced Search Options: Term, author, date, network
7. Public Library of Science
Public Library of Science (PLOS) is a big player in the world of OA science. Publishing 12 OA journals, the nonprofit organization is committed to facilitating openness in academic research. According to the site, “all PLOS content is at the highest possible level of OA, meaning that scientific articles are immediately and freely available to anyone, anywhere.”
PLOS outlines four fundamental goals that guide the organization: break boundaries, empower researchers, redefine quality, and open science. All PLOS journals are peer-reviewed, and all 12 journals uphold rigorous ethical standards for research, publication, and scientific reporting.
PLOS does not offer advanced search options. Content is organized by topic into research communities that users can browse through, in addition to options to search for both articles and journals. The PLOS website also has resources for peer reviewers, including guidance on becoming a reviewer and on how to best participate in the peer review process.
Collection: 12 journals
Other Services: None
Good Source of Peer-Reviewed Articles: Yes
Advanced Search Options: None
8. OpenDOAR
OpenDOAR, or the Directory of Open Access Repositories, is a comprehensive resource for finding free OA journals and articles. Using Google Custom Search, OpenDOAR combs through OA repositories around the world and returns relevant research in all disciplines.
The repositories it searches through are assessed and categorized by OpenDOAR staff to ensure they meet quality standards. Inclusion criteria for the database include requirements for OA content, global access, and categorically appropriate content, in addition to various other quality assurance measures. OpenDOAR has metadata, data, content, preservation, and submission policies for repositories, in addition to two OA policy statements regarding minimum and optimum recommendations.
This database allows users to browse and search repositories, which can then be selected, and articles and data can be accessed from the repository directly. As a repository database, much of the content on the site is geared toward the support of repositories and OA standards.
Collection: 5,768 repositories
Other Services: OpenDOAR offers a variety of additional services. Given the nature of the platform, services are primarily aimed at repositories and institutions, and there is a marked focus on OA in general. Sherpa services are OA archiving tools for authors and institutions.
They also offer various resources for OA support and compliance regarding standards and policies. The publication router matches publications and publishers with appropriate repositories.
There are also services and resources from JISC for repositories for cost management, discoverability, research impact, and interoperability, including ORCID consortium membership information. Additionally, a repository self-assessment tool is available for members.
Good Source of Peer-Reviewed Articles: No
Advanced Search Options: Name, organization name, repository type, software name, content type, subject, country, region
9. Bielefeld Academic Search Engine
The Bielefeld Academic Search Engine (BASE) is operated by the Bielefeld University Library in Germany, and it offers more than 240 million documents from more than 8,000 sources. Sixty percent of its content is OA, and you can filter your search accordingly.
BASE has rigorous inclusion requirements for content providers regarding quality and relevance, and they maintain a list of content providers for the sake of transparency, which can be easily found on their website. BASE has a fairly elegant interface. Search results can be organized by author, title, or date.
From the search results, items can be selected and exported, added to favorites, emailed, and searched in Google Scholar. There are basic and advanced search features, with the advanced search offering numerous options for refining search criteria. There is also a feature on the website that saves recent searches without additional steps from the user.
Collection: 276,019,066 documents; 9,286 content providers
Other Services: None
Good Source of Peer-Reviewed Articles: Yes
Advanced Search Options: Author, subject, year, content provider, language, document type, access, terms of reuse
10. Digital Library of the Commons Repository
Run by Indiana University, the Digital Library of the Commons (DLC) Repository is a multidisciplinary journal repository that allows users to access thousands of free and OA articles from around the world. You can browse by document type, date, author, title, and more or search for keywords relevant to your topic.
DCL also offers the Comprehensive Bibliography of the Commons, an image database, and a keyword thesaurus for enhanced search parameters. The repository includes books, book chapters, conference papers, journal articles, surveys, theses and dissertations, and working papers. DCL advanced search features drop-down menus of search types with built-in Boolean search options.
Searches can be sorted by relevance, title, date, or submission date in ascending or descending order. Abstracts are included in selected search results, with access to full texts available, and citations can be exported from the same page. Additionally, the image database search includes tips for better search results.
Collection: 10,784
Other Services: None
Good Source of Peer-Reviewed Articles: No
Advanced Search Options: Author, date, title, subject, sector, region, conference
11. CIA World Factbook
The CIA World Factbook is a little different from the other resources on this list in that it is not an online journal directory or repository. It is, however, a useful free online research database for academics in a variety of disciplines.
All the information is free to access, and it provides facts about every country in the world, which are organized by category and include information about history, geography, transportation, and much more. The World Factbook can be searched by country or region, and there is also information about the world’s oceans.
This site contains resources related to the CIA as an organization rather than being a scientific journal database specifically. The site has a user interface that is easy to navigate. The site also provides a section for updates regarding changes to what information is available and how it is organized, making it easier to interact with the information you are searching for.
Collection: 266 countries
Other Services: None
Good Source of Peer-Reviewed Articles: No
Advanced Search Options: None
12. Paperity
Paperity boasts its status as the “first multidisciplinary aggregator of OA journals and papers.” Their focus is on helping you avoid paywalls while connecting you to authoritative research. In addition to providing readers with easy access to thousands of journals, Paperity seeks to help authors reach their audiences and help journals increase their exposure to boost readership.
Paperity has journal articles for every discipline, and the database offers more than a dozen advanced search options, including the length of the paper and the number of authors. There is even an option to include, exclude, or exclusively search gray papers.
Paperity is available for mobile, with both a mobile site and the Paperity Reader, an app that is available for both Android and Apple users. The database is also available on social media. You can interact with Paperity via Twitter and Facebook, and links to their social media are available on their homepage, including their Twitter feed.
Collection: 8,837,396
Other Services: None
Good Source of Peer-Reviewed Articles: Yes
Advanced Search Options: Title, abstract, journal title, journal ISSN, publisher, year of publication, number of characters, number of authors, DOI, author, affiliation, language, country, region, continent, gray papers
13. dblp Computer Science Bibliography
The dblp Computer Science Bibliography is an online index of major computer science publications. dblp was founded in 1993, though until 2010 it was a university-specific database at the University of Trier in Germany. It is currently maintained by the Schloss Dagstuhl – Leibniz Center for Informatics.
Although it provides access to both OA articles and those behind a paywall, you can limit your search to only OA articles. The site indexes more than three million publications, making it an invaluable resource in the world of computer science. dblp entries are color-coded based on the type of item.
dblp has an extensive FAQ section, so questions that might arise about topics like the database itself, navigating the website, or the data on dblp, in addition to several other topics, are likely to be answered. The website also hosts a blog and has a section devoted to website statistics.
Collection: 5,884,702
Other Services: None
Good Source of Peer-Reviewed Articles: Yes
Advanced Search Options: None
14. EconBiz
EconBiz is a great resource for economic and business studies. A service of the Leibniz Information Centre for Economics, it offers access to full texts online, with the option of searching for OA material only. Their literature search is performed across multiple international databases.
EconBiz has an incredibly useful research skills section, with resources such as Guided Walk, a service to help students and researchers navigate searches, evaluate sources, and correctly cite references; the Research Guide EconDesk, a help desk to answer specific questions and provide advice to aid in literature searches; and the Academic Career Kit for what they refer to as Early Career Researchers.
Other helpful resources include personal literature lists, a calendar of events for relevant calls for papers, conferences, and workshops, and an economics terminology thesaurus to help in finding keywords for searches. To stay up-to-date with EconBiz, you can sign up for their newsletter.
Collection: 1,075,219
Other Services: None
Good Source of Peer-Reviewed Articles: Yes
Advanced Search Options: Title, subject, author, institution, ISBN/ISSN, journal, publisher, language, OA only
15. BioMed Central
BioMed Central provides OA research from more than 300 peer-reviewed journals. While originally focused on resources related to the physical sciences, math, and engineering, BioMed Central has branched out to include journals that cover a broader range of disciplines, with the aim of providing a single platform that provides OA articles for a variety of research needs. You can browse these journals by subject or title, or you can search all articles for your required keyword.
BioMed Central has a commitment to peer-reviewed sources and to the peer review process itself, continually seeking to help and improve the peer review process. They’re “committed to maintaining high standards through full and stringent peer review.”
Additionally, the website includes resources to assist and support editors as part of their commitment to providing high-quality, peer-reviewed OA articles.
Collection: 507,212
Other Services: BMC administers the International Standard Randomised Controlled Trial Number (ISRCTN) registry. While initially designed for registering clinical trials, since its creation in 2000, the registry has broadened its scope to include other health studies as well.
The registry is recognized by the International Committee of Medical Journal Editors, as well as the World Health Organization (WHO), and it meets the requirements established by the WHO International Clinical Trials Registry Platform.
The study records included in the registry are all searchable and free to access. The ISRCTN registry “supports transparency in clinical research, helps reduce selective reporting of results and ensures an unbiased and complete evidence base.”
Good Source of Peer-Reviewed Articles: Yes
Advanced Search Options: Author, title, journal, list
16. JURN
A multidisciplinary search engine, JURN provides links to various scholarly websites, articles, and journals that are free to access or OA. Covering the fields of the arts, humanities, business, law, nature, science, and medicine, JURN has indexed almost 5,000 repositories to help you find exactly what you’re looking for.
Search features are enhanced by Google, but searches are filtered through their index of repositories. JURN seeks to reach a wide audience, with their search engine tailored to researchers from “university lecturers and students seeking a strong search tool for OA content” and “advanced and ambitious students, age 14-18” to “amateur historians and biographers” and “unemployed and retired lecturers.”
That being said, JURN is very upfront about its limitations. They admit to not being a good resource for educational studies, social studies, or psychology, and conference archives are generally not included due to frequently unstable URLs.
Collection: 5,064 indexed journals
Other Services: JURN has a browser add-on called UserScript. This add-on allows users to integrate the JURN database directly into Google Search. When performing a search through Google, the add-on creates a link that sends the search directly to JURN CSE. JURN CSE is a search service that is hosted by Google.
