Nowadays, farmers and advisors can access numerous tools and methods linked to crop diversification. Some of them express their difficulties to find the most adapted through this jungle. In DiverIMPACTS project, an inventory of existing tools and methods for crop diversification across Europe was conducted in 2018, aiming to identify and characterize them according to their purpose, type, users, and technical characteristics. This is the first step to build a decision tree to support farmers, advisors and other actors along the value chain, to identify the most suitable tool for their situation and needs. This inventory aims to give an overview of the existing tools and methods to promote crop diversification, including all its components (e.g., rotation, multiple cropping, inter-cropping) at the value chain and territory levels. The large scope of this inventory led to identify tools and/or methods created to support crop diversification (with one or more identified strategies), as well as those using crop diversification as a way to achieve an expected impact. The inventory was based on an online survey as well as interviews. 58 responses have been collected from 38 different people from 11 countries. The database contains 42 tools and eight methods from eight different countries. A tool/method often allows users to make several kinds of decisions (e.g., management, design, mobilization of references, diagnosis, assessment) and can mobilize different diversification mechanisms (e.g., rotation, multiple cropping, intercropping) or a combination of different levers. Most of the tools can be implemented at the field or cropping system scale (46/50). Only eight could be used at the territory or value chain level. Different kinds of information about how to mobilize these tools/methods have been registered such as format, language, when to use the tool, training requirements, cost of the tool and contact person or organization. The database describing all of the tools is available and will be incremented during the project with new tools. Eight tools under development (mainly from other H2020 projects) were also identified during the inventory process. They will be added to the database when they become available for end-users.