This paper presents the design and evaluation of HomeNet Profiler, a tool that runs on an end-system in the home to collect data from home networks. HomeNet Profiler collects a wide range of measurements including: the set of devices, the set of services (with UPnP and Zeroconf), and the characteristics of the WiFi environment. Since the release of HomeNet Profiler in April 2011, we have collected data from over 2,400 distinct homes in 46 different countries.