We report on progress towards creating an interactive place-based carbon calculator for England. The purpose of the calculator is to enable policymakers and the public to understand the spatial variation in per capita carbon footprint and monitor progress towards decarbonisation. The calculator will be launched in the summer of 2021 as a free web tool. The paper highlights the challenges and methods used to calculate carbon footprints for small areas and how new developments in web mapping can enable the presentation of large complex spatial datasets with minimal cost.