Soil organic carbon (SOC) is central to soil health and the global carbon cycle, as it represents the largest terrestrial carbon pool. SOC stocks are strongly affected by agricultural management. Unsuitable management often leads to SOC loss and soil degradation, while adapted management sustains or enhances SOC content in agricultural soils. Understanding and quantifying the impact of management on SOC dynamics is therefore critical for agricultural sustainability and climate mitigation. Here, we present results of a biogeochemical model-based tool to estimate the effects of farm management on long-term SOC stock dynamics in Swiss croplands under varying management actions and climate scenarios. The tool integrates well-established models, such as RothC, DayCent and AMG, and was calibrated using long-term management and SOC measurement data from the Swiss Soil Monitoring Network (NABO) and field trials. By combining multiple national datasets, including information on soil properties, weather conditions, land use types, and manure management, the tool reduces the data input requirements for users. The resulting platform will be designed to enable field-scale simulations of SOC stock dynamics, offering farmers, advisors, and policymakers a science-based tool to evaluate the influence of management options on soil health. The overarching goal is to promote sustainable soil management and support national agricultural objectives.