Information and communication technology accounts for 3–4% of global emissions, and the sector’s energy consumption is expected to increase significantly, particularly due to the growing demand for data centres. This poses challenges for Finland’s energy self-sufficiency and climate targets. The project will develop an open-access and free online calculator that estimates the energy consumption and emissions of software, artificial intelligence, and digital devices. The calculations are based on measurements, open emission databases, and region-specific emission factors. The tool provides reliable recommendations for optimising energy use and reducing emissions. The solution supports organisations in improving energy efficiency, achieving emission reduction targets, and promoting responsible digitalisation. Its novelty lies in a comprehensive, transparent, and open-source calculation infrastructure that is scalable and integrable into corporate sustainability (ESG) reporting. The project is implemented in the Uusimaa region, but its results will be applicable nationwide.