How this works
The calculator works out two numbers and plans for the bigger one:
- Coverage: about one business-grade access point for every 1,500 square feet of open space. Walls make the signal weaker, so offices with meeting rooms count as 1.3 times their size and brick, concrete or glass as 1.7 times.
- Capacity: about 35 active devices per access point, or 25 when people make lots of video calls, which need steady, fast connections.
Every floor gets at least one access point. These are the planning numbers many installers start from; a site survey measures your real building and can move the number up or down.
Example: a two-floor office with an open plan
An open-plan office of 10,000 square feet over two floors, with 80 people and about 2.5 devices each, and few video calls.
| Input | Value |
|---|---|
| Office floor area (all floors together) | 10,000 sq ft |
| Number of floors | 2 floors |
| What the space is like | Brick, concrete, glass walls or many small rooms |
| People working there at the same time | 80 people |
| Wi-Fi devices per person | 2.50 devices |
| Do people make lots of video calls (Teams, Zoom) over Wi-Fi? | No |
| Result | Value |
| Access points needed for coverage | 7 |
| Devices on Wi-Fi at busy times | 200 |
| Access points needed for the number of devices | 6 |
| Access points to plan for | 7 |
| What drives the number | The floor area and walls set the count here. Put access points on the ceiling, near the middle of each area, away from metal and thick walls. |
Why one big router isn't enough
A home-style router in a closet can reach a long way, but in an office it runs out of capacity long before it runs out of range. Every laptop and phone shares the same airtime, so one access point with 60 devices feels slow for everyone, even on a fast internet line.
Several smaller access points on the ceiling, each serving the people nearby, give a stronger signal and more airtime per person. Business systems also hand a laptop from one access point to the next as people walk between rooms, without dropping a call.
Where to put access points
Good placement matters as much as the number:
- Mount them on the ceiling or high on a wall, not in a cabinet or behind a TV.
- Put them where people work, not where the network cable happens to end.
- Keep them away from metal shelving, elevators, refrigerators and fish tanks.
- In buildings with brick or concrete walls, plan one in each larger room.
Each access point needs a network cable for data and power (PoE). Cabling is often the biggest part of the job in older buildings, so plan it early.
Guests, printers and smart devices
Keep guests and smart devices (TVs, cameras, thermostats) on their own Wi-Fi network, separate from the computers that hold your business data. Most business access points can run several networks at once. Count guests' phones in the devices per person if you have a waiting room, a classroom or a busy lobby.
When to get a site survey
Use this estimate for budgeting. Before you buy, a short site survey measures the real signal in your building, finds sources of interference and shows exactly where each access point should go. It's especially worth it for older buildings, warehouses, medical offices and anywhere with thick walls. We can do one for offices across Maryland, DC and Northern Virginia.