How this tool works
A PoE switch has one total power budget that is usually lower than ports multiplied by the per-port limit. Add up the maximum draw of each device, keep about 20% in reserve, and compare the total with the switch budget. The per-device watts are typical values you can edit; check the datasheet for the exact maximum.
Common questions
What is the difference between 802.3af, 802.3at and 802.3bt?
802.3af (PoE) delivers up to 15.4 W per port, 802.3at (PoE+) up to 30 W, and 802.3bt (PoE++) up to 60 W or 90 W. A device that needs more than the port can give will not start or will keep rebooting.
Why keep 20% in reserve?
Devices draw more power when they start, when cameras switch on infrared night vision, and some power is lost in the cable. A reserve stops ports shutting down when many devices peak together.
Can a 24-port PoE switch power 24 devices?
Not always. Many 24-port switches have a budget of 185 to 370 W, which suits cameras and phones but is too low for 24 Wi-Fi 6 access points. Always compare the total budget, not the port count.
