arXiv is an e-print service in the fields of physics, mathematics, computer science, quantitative biology, quantitative finance, statistics, electrical engineering and systems science, and economics. It provides access to more the 1.3 million e-prints. The Max Planck Society is a member institution of arXiv.

BASE is a multidisciplinary search engine for scholarly internet resources which have been harvested from several hundred scientific repositories. Some of the indexed resources in BASE are subject to license, while most material is free available ("open access").

BioMed Central is an STM (Science, Technology and Medicine) publisher of 270 peer-reviewed open access journals. The portfolio of journals spans all areas of biology, biomedicine and medicine and includes broad interest titles, such as BMC Biology and BMC Medicine alongside specialist journals, such as Retrovirology and BMC Genomics. The Max Planck Society is a BMC member and covers article-processing charges for Max Planck authors centrally. Further details are available on the MPDL website.

Welcome to CogPrints, an electronic archive for self-archive papers in any area of Psychology, neuroscience, and Linguistics, and many areas of Computer Science (e.g., artificial intelligence, robotics, vision, learning, speech, neural networks), Philosophy (e.g., mind, language, knowledge, science, logic), Biology (e.g., ethology, behavioral ecology, sociobiology, behaviour genetics, evolutionary theory), Medicine (e.g., Psychiatry, Neurology, human genetics, Imaging), Anthropology (e.g., primatology, cognitive ethnology, archeology, paleontology), as well as any other portions of the physical, social and mathematical sciences that are pertinent to the study of cognition.

The DOAJ service lists toll-free, quality controlled, scientific and scholarly journals. It generally aims at covering all subjects and languages. The DOAJ Articles Search is restricted to those journals the publisher has supplied article metadata for.

The EZB is a huge directory of electronic journals which mirrors the central Max Planck Society subscriptions as well as the local licensing situation of the institutes. Access rights to the contents of the individual journals are indicated with "traffic lights". Entries are searchable on journal level.

Google Book Search is a service from Google that searches the full text of books that Google scans, converts to text using optical character recognition, and stores in its digital database.

The goal of OAIster is to create a collection of previously difficult-to-access, academically-oriented digital resources that is easily searchable by anyone.

The Open Library of Humanities is an open access publishing platform, launched as an international network of scholars, librarians, programmers and publishers in January 2013. The OLH platform supports academic journals from across the humanities disciplines, as well as hosting its own multidisciplinary journal. Unlike many open-access publishers, the Open Library of Humanities does not charge individual author fees, but covers all costs by cooperating with an international library consortium.

The OSF Preprints search combines records from various preprint repositories, including arXiv, bioRxiv, Cogprints, PeerJ, PsyArXiv, RePEc and SocArXiv.

SciPost is a complete scientific publication portal managed by and for scientists. It is purely online-based, and offers freely, openly, globally and perpetually accessible science (open access). Preprint handling and circulation occurs through the well-established arXiv; the rest of the publication process, from peer refereeing through publication all the way to post-publication commenting, is offered by SciPost. SciPost does not charge individual author fees, the Max Planck Society is a supporting partner of the project.