NMRShiftDB is a web database for organic structures and their nuclear magnetic resonance (nmr) spectra. It allows for spectrum prediction (currently only for carbon) as well as for searching spectra, structures and other properties. Last not least, it features peer-reviewed submission of datasets by its users.

Nomos eLibrary provides access to academic books and journals in the subject areas of law, political sciences, economics, media and communication sciences, history, sociology, education and cultural studies, European Union, health sciences. The book selection has been continuously extended through the acquisition of individual eBook packages by MPG libraries. From volume 2022 onwards, access is given to the complete Nomos eBook portfolio. Max Planck researchers can publish their scientific work with Nomos as a print and in parallel as an Open Access eBook in the Nomos eLibrary. Further details are available on the MPDL website.

O'Reilly is an electronic reference library by providing access to technical content from leading publishers, including books, videos, proven learning paths, case studies, interactive tutorials and audio books. The learning platform gives access to the latest titles from O'Reilly and from Pearson's collection of imprints which include: Addison-Wesley Professional, Adobe Press, Cisco Press, Macromedia Press, New Riders, Peachpit Press, Prentice Hall PTR, Sun Microsystems Press, Que, and Sams. Microsoft Press titles are also available in O'Reilly.

OLC Chemistry is a subject oriented selection of bibliographic data from the Database Online Contents. This database is regularly enhanced by table of contents data from additional periodicals out of the special collections of TIB Hannover.

OLC Economic Sciences is a subject oriented selection of bibliographic data from the Online Contents database that is regularly enhanced by table of contents data from 3,150 additional periodicals with more than 4,500,000 records of articles out of the special collections of the ZBW – Leibniz-Informationszentrum Wirtschaft and the university library of the Helmut Schmidt university, Federal Armed Forces, Hamburg.

The database OLC Mathematics and Informatics is a subject oriented selection of bibliographic data from the Online Contents database that is regularly enhanced by table of contents data from additional periodicals out of the special collections of the TIB Hannover. Currently 1,357 journals are being indexed back to the year of publication in 1993.

The Online Contents service of the Special Subject Collection Political Science and Peace Research is part of the Online Contents database. It offers access to tables of contents of more than 870 journals relevant for study and research. New journals were added until December 2013 by the Special Subject Collection. Thus the database contains approximately 1.478,600 records of journal articles and reviews.

OLC Psychology is a subject oriented selection of bibliographic data from the Online Contents database. This database is regularly enhanced by table of contents data from additional periodicals out of the special collections of the Saarland University and State Library (SULB) Saarbrücken, the central subject library for Psychology in Germany. Currently 878 journals are being indexed back to the year of publication in 1993.

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

Developed cooperatively with scholars and librarians worldwide, Oxford Bibliographies offers exclusive, authoritative research guides across a variety of subject areas. Combining the best features of an annotated bibliography and a high-level encyclopedia, this cutting-edge resource directs researchers to the best available scholarship across a wide variety of subjects.

Oxford Handbooks Online is a collection of handbooks in 17 subject areas, bringing together the world's leading scholars to write review essays that evaluate the current thinking on a field or topic, and make an original argument about the future direction of the debate. For the first time, all Handbooks are available online as well is in print across the subject areas. Monthly updates introduce articles in advance of print publication and beyond the book, online-only content ensures the most current, authoritative coverage anywhere.

Including Oxford Scholarship Online (OSO), the University Press Scholarship Online (UPSO) publishes new books every month from an ever-growing roster of contributing presses, each adding to the variety of subjects covered on the platform. The MPG purchased the volumes 2003-2013/2014 of 16 OSO subject collections. This selection is continuously extended by single e-book acquisitions by MPG libraries.

Periodicals Archive Online is a major archive that makes the backfiles of scholarly periodicals in the arts, humanities and social sciences available electronically, providing access to the searchable full text of hundreds of titles. The database spans more than two centuries of content, 37 key subject areas, and multiple languages.

This historic journal index enables the simultaneous search in millions of citations for articles published in the arts, humanities and social sciences, across more than 300 years. It enables researchers quickly and comprehensively to identify articles relevant to their field of study and reduces what could take years of research to a matter of minutes. Journals indexed span 37 key subject areas and multiple languages.

Portland Press Limited, the wholly-owned trading subsidiary of the Biochemical Society, is a leading innovative publisher of journals, books and electronic resources. The platform provides Max Planck researchers with selective access to the full texts of journals owned by the Biochemical Society, see link "eJournals licensed" below. The MPG subscription also covers article-processing charges for Max Planck authors in all Portland Press/Biochemical Society journals. Further details are available on the MPDL website.

Project MUSE is a leading provider of digital humanities and social science content for the scholarly community. Since 1995 the MUSE journal collections cover full-text versions of scholarly journals from many of the world's leading university presses and scholarly societies, with over 120 publishers currently participating.

PsycARTICLES comprises journals published by the American Psychological Association, the APA Educational Publishing Foundation, the Canadian Psychological Association, and Hogrefe Publishing Group, from 1894 onwards.

PsycCRITIQUES contains full-text reviews of books in psychology and the social sciences, as well as professional videos and popular films from a psychological perspective. Reviews occasionally include comparative or retrospective book reviews. The database also includes all reviews published in the print journal Contemporary Psychology: APA Review of Books between 1956 (Volume 1, Issue 1) and 2004. PsycCRITIQUES ended publication in Fall 2017, the archive is made available by the CCHP in partnership with the APA.

The PsycINFO databases cover the professional and academic literature in psychology and related disciplines including medicine, psychiatry, nursing, sociology, education, pharmacology, physiology, linguistics, and other areas. Coverage is worldwide, and includes references and abstracts to over 1300 journals and to dissertations in more than 30 languages, and to book chapters and books in the English language. Over 50,000 references are added annually. Popular literature is excluded.

The PsyJOURNALS collection is a diverse portfolio of highly-regarded, peer-reviewed journals in German and English languages published by Hogrefe and by Hans Huber that cover a wide range of areas within psychology and psychiatry. Max Planck researchers have full text access to 31 journals from 2015 onwards, with a two-year moving wall.