If you feel like your Xfinity home connection or your Xfinity WiFi hotspot is slow, try measuring the WiFi signal strength with an app like NetSpot. In the app open the Discover mode. You’ll see a report on all surrounding WiFi networks, with the information about their WiFi band, average signal strength, level of noise, the encryption method, etc.
This data can be used to assess your WiFi connection, e.g. the first thing you look at is the level of your network’s wireless signal — if it is strong, then the slow Internet speed is caused by a different issue, and you go from there.