LoRaWAN Capacity Planning Workbench
Estimate airtime, channel load, duty pressure, ADR impact, and downlink bottlenecks before a LoRaWAN fleet is deployed.
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Interactive LoRaWAN capacity workbench that links spreading-factor mix, payload size, report interval, gateway count, regional assumptions, and confirmed uplinks to visual channel load and planning headroom.
LoRaWAN Capacity Planning Workbench
Explore how spreading-factor mix, payload size, report interval, gateways, channel plan, and confirmed uplinks combine into a capacity decision. The result is a planning estimate, not a packet-level network simulator.
Ready
planning verdict
0%
of shared-airtime budget
0
estimated devices at this budget
RF load
current limiting factor
1. Airtime changes first
Higher spreading factors keep each packet on the channel longer, so the same payload can consume very different RF time.
2. Capacity is shared
Gateways hear many channels, but all devices still contend with other devices, repeats, interference, and the selected channel plan.
3. Regulations matter
Duty-cycle, dwell-time, and channel rules vary by regional parameter set and local regulation. Treat the selected limits as planning assumptions.
4. Downlinks do not scale freely
Confirmed uplinks create gateway transmissions. At fleet scale, ACK airtime can become the bottleneck before uplinks do.
Airtime
Compute LoRa packet duration from SF, bandwidth, coding rate, and bytes.
Fleet traffic
Multiply airtime by devices, interval, and repeat count.
Shared channels
Compare offered load with the chosen planning budget.
Downlinks
Estimate ACK pressure from confirmed uplinks.
Decision
Identify the bottleneck and the next capacity lever.
Scenario
Balanced city sensors with ADR and sparse acknowledgments.
Ready with headroom
This configuration fits the selected planning budget. Growth and site validation still matter.
0 ms
weighted uplink airtime
0%
device transmit duty
0%
downlink budget pressure
0%
ALOHA collision proxy
SF7
0 ms, 0% of fleet
SF9
0 ms, 0% of fleet
SF10
0 ms, 0% of fleet
SF12
0 ms, 0% of fleet
Capacity diagnosis
The selected fleet leaves enough shared-airtime margin for retries, interference, and growth.
Best next lever
Keep ADR enabled for stationary devices and avoid unnecessary confirmed uplinks.
Model assumptions
125 kHz LoRa, explicit header, CRC on, coding rate 4/5, 8-symbol preamble, plus an estimated 13 bytes of LoRaWAN frame overhead.
Formula Trace
LoRa packet airtime
Tsym = 2^SF / BW; ToA = (preamble + 4.25 + payloadSymbols) * Tsym
Low-data-rate optimization is enabled in the estimate for SF11 and SF12 at 125 kHz.
Offered uplink load
airtime/hour = reports/hour * weighted ToA * repeats
The workbench compares offered RF time with a conservative shared-airtime planning budget, not a theoretical maximum.
Downlink pressure
ACK airtime/hour = confirmed reports/hour * conservative ACK ToA
Confirmed uplinks can be limited by gateway downlink availability, receive-window timing, and regional rules.
Collision proxy
risk ~= 1 - exp(-2G)
This unslotted ALOHA proxy is only a warning signal; gateways, capture effect, interference, and timing distribution change real results.
Technical Notes And References
What this model deliberately avoids
- It does not claim different spreading factors are perfectly independent capacity pipes.
- It does not replace region-specific certification, local radio regulations, or a network server simulator.
- It treats ADR as a distribution choice, not a guaranteed percentage improvement.
Capacity planning cautions
- SF12-heavy fleets can be airtime limited even when message counts look small.
- Shorter payloads and longer report intervals are often stronger than adding one gateway.
- Confirmed uplinks should be reserved for traffic that truly needs MAC-layer acknowledgement.