Estimate internet and wireless airtime capacity for a WiFi deployment from device count, peak activity, application demand, protocol efficiency, and headroom. The calculator separates payload demand from required raw wireless capacity and suggests how many equal-capacity radios are needed.
Payload bandwidth helps size the internet path; raw WiFi capacity reflects the extra channel time required by wireless efficiency. Radio count is a capacity-only estimate and does not replace coverage or channel planning.
PHY rates are not application throughput. Interference, client capabilities, contention, channel width, band selection, roaming, and coverage can require more radios than this capacity model.
For 300 devices with 40% active at 5 Mbps each, payload demand is 600 Mbps. With 25% headroom and 55% usable efficiency, required raw wireless capacity is 1,363.64 Mbps, or 2 radios at 1,200 Mbps each.
It is application payload throughput divided by raw wireless capacity. Protocol overhead, contention, retries, and airtime behavior make it lower than 100%.
Payload demand informs internet and wired backhaul needs. Raw WiFi capacity and radio count address the wireless side of the model.
Coverage, client density, channel reuse, interference, roaming, redundancy, or per-radio client limits can exceed the capacity-only minimum.
Use expected average demand for an active device during the busy period. A maximum requirement can be tested as a separate conservative scenario.
You can enter it, but advertised aggregate PHY rates may overstate deployable capacity. A validated planning value produces a more useful estimate.
| Input | Purpose |
|---|---|
| Connected devices | User-adjustable planning assumption |
| Simultaneously active devices | User-adjustable planning assumption |
| Average Mbps per active device | User-adjustable planning assumption |
| Usable WiFi efficiency | User-adjustable planning assumption |
| Capacity headroom | User-adjustable planning assumption |