Walter De Gruyter publishes a wide variety of content covering humanities, medicine, the sciences and law. The "De Gruyter Online" platform provides access to title information and the electronic content for De Gruyter journals and books under one roof. Users from the MPG have access to following products: * De Gruyter Journals and Yearbooks - current content of selected serial titles available on the platform (last 13 volumes) * De Gruyter Journal Archive - backfile content of 150 titles * De Gruyter Online / Research Now E-Journal Archive - about 50 journals focusing on research in economics, formerly published by Berkeley Electronic Press until 2022 * De Gruyter eBooks - a collection of purchased e-books which is continuously extended by single e-book acquisitions by MPG libraries

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.

The Max Planck Journal Index provides holdings of a great range of printed journals available within the Max Planck Society. Besides, it contains metadata of electronic journals as loaded from the EZB. The database is updated regularly from the ZDB (twice a year) and the EZB (monthly).

The ZDB is the world’s largest specialized database for serial titles (journals, annuals, newspapers etc., incl. e-journals). The ZDB contains more than 1 million bibliographic records of serials from the 16th century onwards, from all countries, in all languages, held in 4000 German (and some foreign) libraries, with holdings information. It does not index individual journal articles.