Reddit karma is one of the many things which WunderCharts can track. You can track your own Reddit karma, or somebody else's. When you begin tracking a Reddit user, WunderCharts immediately begins tracking both kinds of Reddit karma, which are link karma and comment karma.
If you already have a WunderCharts account, begin tracking Reddit karma by logging in to your account and the clicking on Reddit from the Trackers page. If you don't yet have a WunderCharts account, choose the signup link and choose Reddit from the list of supported services.