Increasingly frequent around the world, heat waves are affecting Canada, where their frequency and intensity are increasing with climate change. This threat weighs on the health of the population, as oppressive heat is associated with increased mortality and many health problems. The vulnerability and exposure of the population vary over time and space, placing certain groups at greater risk. The effects of heat waves on the health and well-being of communities are mostly modulated by people’s ability to access resources. The main objective of this project is to develop an interactive online mapping application that provides valid information on the geographical distribution of populations’ vulnerability and exposure in 156 urban regions of the country, specifying their intensity at the residential dissemination area scale. The tool is intended for professionals in the field while remaining accessible to the general public. Four indices were calculated (sensitivity, coping capacity, vulnerability, and exposure) based on socio-economic, demographic, proximity to services, and characterization of the built and natural environment data associated with the population’s vulnerability and exposure to extreme heat waves. A map of urban heat islands has also been produced.