To determine if your router is a Gigabit router, you can check the specifications or documentation that came with the device. Look for the term "Gigabit" or "10/100/1000" in the product name or description. Alternatively, you can check the network ports on the back of the router. Gigabit routers typically have one or more Ethernet ports labeled as "10/100/1000" or "Gigabit." If your router has only "10/100" ports, it is not a Gigabit router and can support a maximum data transfer rate of 100 megabits per second.