The Western Balkans Climate Data Viewer is part of the report on „Impacts of climate change on agriculture and recommendations for adaptation measures in the Western Balkans“ published by SWG RRD, IAMO and GFA Consulting Group. It contains a collection of several hundreds of maps about climate change in the Western Balkans. The user can choose between historical and future trends of different climatic and extreme weather indicators such as temperature, precipitation, heat and frost. All data has been aggregated for two major crop growth periods: Maize (Apil – October) and Wheat (October – July). The historical trends summarize the municipality-level changes in climate and weather over the period from 1992 to 2020 and are based on precipitation data from CHIRPS and temperature data from ERA5-Land. The future trends are based on climate change projections provided by ISIMIP and are available at a 0.5 degree spatial resolution. For the future trends, the user can choose between two climate change scenarios (RCP 4.5 and RCP 8.5) and two future time periods (2040-2060, and 2080-2100). With this data viewer, we aim to improve the understanding of the spatial patterns of climate change in the Western Balkans, and inform about the severity of ongoing changes in temperature and precipitation patterns and their potential negative effects on agricultural production in the region.