For decades, a continuous loss of species diversity in the agricultural landscape has been observed. Today, not only are conservationists and governments engaged in halting the decline of farmland species diversity, but so too are actors of food production and retail. They are aware of the crucial role that farmers play in preserving and promoting species diversity. Food companies would therefore like to record and document the contribution their supplier farmers make to the conservation of biodiversity by managing their land and to show which measures can further promote biodiversity on the farms. Existing valuation approaches and advisory systems that have been applied in practice are either very complicated and time consuming or they are adjusted to assess individual farms by advisory services. The resulting case-specific evaluation is based on the assessment and experience of the consultant and is therefore not necessarily comparable across different farms. There is, therefore, no scientifically sound evaluation system that can simply, comprehensibly and justifiably map the current value and changes in habitats and species richness on farms. In order to ensure the necessary practical relevance and the widest possible dissemination of the results, the research project “Firmen fördern Vielfalt” (companies foster biodiversity) has been implemented. In this project, a system was developed that uses easy-to-grasp key indicators to model species richness on farms. By using a modelling approach, habitat and species richness assessments could be automated and therefore repeated over time. Thus, the evaluation of habitat types is improved in such way that changes in response to modified management practices can be shown. This makes the biodiversity performance of farms measurable and comparable. The working paper explains the methodology and shows main results of the project. The research was carried out by the Institute of Environmental Planning at the Leibniz University Hannover, in cooperation with the Association of Organic Food Processors (AöL), the Chamber of Agriculture Lower-Saxony and the Advisory Service for Bioland Farmers. The food companies Bionade, Hipp, Märkisches Landbrot and Neumarkter Lammsbräu supported the project.