ℹ️ Preview calculator: calculation logic is still being verified. Output may not reflect realistic engineering values. Details

MAC Address Table Calculator

Estimate MAC address table capacity needs and memory usage

Total number of active switch ports. Includes access ports, trunk ports, and uplinks. Each port learns MAC addresses from connected devices.
Average number of MAC addresses learned per port. Access ports typically learn 1-5. Trunk/uplink ports can learn hundreds or thousands.
seconds
The hardware MAC address table size of the switch. Exceeding this limit causes unknown unicast flooding, degrading performance and security.

MAC Table Results

Total MAC Entries Needed
Switch Capacity
Table Utilization
Memory Estimate
Remaining Capacity
Aging Time
References:
MAC entry: ~12 bytes (6B MAC + 2B VLAN + 2B port + 2B flags)
Table overflow causes unknown unicast flooding
Cisco default aging time: 300 seconds