An Ethernet switch expands wired connectivity without replacing your router. Start by assessing port count: a five-port switch uses one port for the router uplink, leaving four for devices, while an eight-port model offers seven usable ports for future growth. Speed is critical — match the switch to your network's capabilities. A 1GbE switch suffices for Gigabit internet and devices, but 2.5GbE avoids bottlenecks with multi-gig internet, 2.5GbE PCs, or fast NAS units, and runs on existing Cat5e cabling. 10GbE benefits local transfers like large NAS backups but costs more.

Most homes need only an unmanaged switch — plug-and-play with no configuration. Managed or smart switches add VLANs, QoS, and traffic monitoring for complex setups but cost extra. Power over Ethernet (PoE) powers devices like cameras and access points via the cable, but check the switch's total power budget, not just port count, to ensure it supports all devices simultaneously.

Physical design matters: fanless models suit visible areas, while larger actively cooled switches belong in network closets. Choose based on current needs with room to grow, avoiding overpriced features you won't use.