As we continue to confront the COVID-19 pandemic, one could argue that never before has timely and accurate population data been so critical. Population data is necessary to understand everything from the spread of the virus and who is impacted, to where vulnerable populations are located, and levels of population density for establishing effective social-distancing measures. And gridded population data are playing an important role in helping researchers access this type of information. Gridded population maps distribute data using grid cells, combining census results with additional information, such as geospatial data from satellites, to ensure more frequent and granular estimates, which are vital during a constantly evolving epidemic. In this blog, we explore how gridded population data are being used by researchers to inform the COVID-19 response.