Why scale by deployment uptime?

Few rollouts hit every site every week. Deployment uptime captures the share of time the team is actually progressing through the schedule.

What is a typical clean-install rate?

90 to 98 percent for mature gateways with stable revisions. New product introductions often run lower; account for that in the order quantity.

Should I include sensors here too?

Use this calculator for edge gateways and IPCs. Use the sensor installation cost calculator for sensor count and cost; the unit economics are different.

How do I size the spare-pool?

Take the DOA / damage loss number and add a small buffer (typical 10 to 30 percent) to cover field replacement turnaround.

IIoT, SCADA & Edge Connectivity calculator

Edge Device Count Calculator

Estimate edge device count for a rollout. Enter sites in scope, devices per site, deployment uptime headroom (share of period the deployment is actually advancing), and the share of devices that go in cleanly without needing a replacement. The calculator returns gross device count, devices that land cleanly, and the loss buckets.

What this calculator does

Estimate the count of edge devices needed in a rollout from sites in scope, devices per site, deployment uptime headroom (share of period the deployment is actually proceeding), and the share of devices that go in cleanly without rework.
Use it when an IIoT program lead is sizing the total edge device order across a multi-site rollout, before placing the hardware PO.
It returns the gross edge device count for a rollout and the count expected to land cleanly inside plan.

Formula used

Gross edge devices needed = sites × devices per site
Edge devices landing cleanly in plan = gross devices × deployment uptime × clean-install rate

Inputs explained

Sites in scope: Use the count of sites in the rollout (plants, distribution centers, or remote pads).
Edge devices per site: Use the architecture standard (typical 1 to 6 edge gateways, IPCs, or wireless gateways per site depending on size).
Deployment uptime headroom: Use the share of the rollout period the deployment team is actually progressing (excluding holidays, customer freezes, weather).
Clean-install rate: Use the share of devices that go in cleanly without needing a replacement (typical 90 to 98 percent; the rest are damaged in transit, dead on arrival, or wrong revision).

How to use the result

Use it before placing the hardware PO for a multi-site rollout, when sizing the spare-pool, or when deciding whether to drop-ship or stage at a regional hub.
It is a count tool. Build a separate spare and rotation plan for replacements that come out of the DOA gap; do not assume the loss number equals spare-pool size.

Common questions

Why scale by deployment uptime? Few rollouts hit every site every week. Deployment uptime captures the share of time the team is actually progressing through the schedule.
What is a typical clean-install rate? 90 to 98 percent for mature gateways with stable revisions. New product introductions often run lower; account for that in the order quantity.
Should I include sensors here too? Use this calculator for edge gateways and IPCs. Use the sensor installation cost calculator for sensor count and cost; the unit economics are different.
How do I size the spare-pool? Take the DOA / damage loss number and add a small buffer (typical 10 to 30 percent) to cover field replacement turnaround.

Last reviewed 2026-05-12.