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PoE Power Budget Calculator

Check whether a PoE switch can carry its powered devices, and see whether watts or ports run out first.

per-port power at the switch
watts available to all PoE ports
powered ports on the switch
watts the device needs at the port
cameras, phones, access points
Enter a budget, port count and device draw to check the load.

The load is the device count multiplied by the draw per device, and the per-port limit is the switch-side power of the chosen standard: 15.4 W for 802.3af Type 1, 30 W for 802.3at Type 2, 60 W for 802.3bt Type 3 and 90 W for Type 4. Devices supported by power is the budget divided by the draw per device, rounded down; devices supported by ports is simply the port count, so the smaller of the two is what the switch can actually carry. Spare headroom is the budget minus the load, and a negative value means the switch is over budget. Cable loss is not modelled: the standards reserve roughly 2.5 W per port for the cable, which is why a 15.4 W port guarantees about 12.95 W at a 100 m device. Redundancy, per-port class negotiation, inrush and thermal derating are also not modelled. Everything runs in your browser with no storage, uploads or network access.