Abstract Energy efficiency is priority number one in the EU in the last two years and efforts to achieve it have been made in various ways: through regulations, guidelines, good practice results, education and training. The buildings sector still is the larger consumer of energy, so many policies and national energy strategies have prepared ambitious goals to significantly decrease the sector’s energy consumption. An important step for the implementation of these strategies is the detection of the potential to energy renovate the existing building stock. This is the objective of this study; to present the ENERFUND tool which displays the current energy performance of a group of buildings and pinpoints the energy renovation potential for the selected buildings. An extensive study to identify the expectations of the future users was carried out, which provided valuable feedback for the features of the tool. The tool utilizes data from publicly available Energy Performance Certificates in the form of an interactive web map and combines them with other geo-referenced data and general information to allow for a rating of deep renovation opportunities. The paper explains the various features of the tool, and presents typical examples of the tool use for targeted stakeholder interests.