Capacity and coverage: the two access point numbers
An access point is the unit that turns a network cable or mesh link into WiFi. Each one can only serve so many devices well, and each one only reaches so far. Those two limits give you two separate access point counts, and the one that matters is whichever comes out higher.
Capacity is about crowding. Even with strong signal, too many devices on one access point means each gets a smaller slice of airtime, and everything slows. Coverage is about distance and obstacles: a big, lightly used space can have plenty of capacity per access point and still have dead corners. Event halls tend to be capacity-limited; warehouses and multi-room sites tend to be coverage-limited. The event network planner runs both counts for you.
How many devices per person to plan for
Access point capacity is counted in devices, so the first job is turning a headcount into a device count.
| Who is connecting | Devices per person | Why |
|---|---|---|
| Working teams (offices, site crews, project staff) | 1.5–2 | A laptop and a phone each, sometimes a tablet, most of them active through the day |
| Conference delegates and workshop attendees | 1.5–2 | Laptops come out in sessions and phones come out in breaks |
| Public event attendees (festivals, markets, community events) | About 1 | Mostly phones, and often fewer are active at once |
| Exhibition stand staff | 1.5–2 | Laptops, tablets, phones and demo devices on each stand |
| Fixed devices (EFTPOS, scanners, screens, cameras) | Count each one | Easy to forget, and they must stay connected |
Planning starting points only. A walk-through or floor-plan review confirms the real mix.
How to calculate the number of access points
If you're planning your own setup, these steps apply whether you use wireless access points on cable or mesh nodes.
Count devices
Multiply each group's headcount by its devices per person, then add the fixed devices. Use the higher end of the range when you're unsure.
Divide by about 50 for capacity
Roughly 50 devices per access point is a widely used starting point for high-density design. Round up: 120 devices ÷ 50 = 2.4, so three access points.
Divide floor area by about 900 m² for coverage
That's our planning assumption for open floor. Round up again: 2,000 m² ÷ 900 = 2.2, so three access points before obstacles.
Adjust for the building
Add access points for internal walls, steel structures, racking, mezzanines and separate levels. Rooms behind solid walls usually need their own.
Take the larger number
Whichever count is higher becomes the starting design. Then check it on site, because the building always has the final say.
Access points for 30, 60, 100, 200, 500 and 1,000 people
Capacity only, at about 50 devices per access point. Check the coverage count for your floor area separately and use whichever is higher.
| Headcount and audience | Devices | Capacity calculation | Access points (capacity) |
|---|---|---|---|
| 30 working people | 45–60 | 60 ÷ 50 = 1.2 | 2 |
| 60 working people | 90–120 | 120 ÷ 50 = 2.4 | 3 |
| 100 public attendees | About 100 | 100 ÷ 50 = 2 | 2, more if the crowd packs into one spot |
| 100 working people | 150–200 | 200 ÷ 50 = 4 | 4 |
| 200 conference delegates | 300–400 | 300 ÷ 50 = 6; 400 ÷ 50 = 8 | 6–8, depending on how many carry laptops |
| 300 public attendees | About 300 | 300 ÷ 50 = 6 | 6 |
| 500 public attendees | About 500 | 500 ÷ 50 = 10 | 10 |
| 500 working people or exhibitors | 750–1,000 | 750 ÷ 50 = 15; 1,000 ÷ 50 = 20 | 15–20 |
| 1,000 public attendees | About 1,000 | 1,000 ÷ 50 = 20 | 20, as a high-density layout |
Always round up. Large crowds need more than arithmetic: channel planning and placement matter as much as the count.
Coverage check: floor area to access points
Our planning assumption is roughly one access point per 900 m² of open floor. Walls, steel, racking and extra levels push the number up.
| Space | Floor area | Coverage calculation | Starting count |
|---|---|---|---|
| Function room | 400 m² | 400 ÷ 900 = 0.4 | 1 |
| Hall or open-plan office | 1,500 m² | 1,500 ÷ 900 = 1.7 | 2 |
| Exhibition floor | 3,000 m² | 3,000 ÷ 900 = 3.3 | 4 |
| Warehouse with upstairs offices | 5,000 m² | 5,000 ÷ 900 = 5.6 | 6, matching our case study |
| Outdoor site | Varies | Line of sight and mounting height decide | Plan from a site walk |
Open floor only. Each solid wall, steel partition, racked aisle or extra level can need an access point of its own.
Worked example: when coverage beats capacity
A 5,000 m² warehouse with upstairs offices, with a team of 50+ people moving in. Capacity first: 50 people × 2 devices = 100 devices, and 100 ÷ 50 = 2 access points. On capacity alone, two would do.
Coverage tells a different story: 5,000 m² ÷ 900 = 5.6, rounded up to six. That's what the real project needed. Six tri-band mesh nodes went in, and every spot tested across the floor and the upstairs offices had full signal. The 5,000 m² warehouse case study walks through it. Two access points would have handled the device count and left most of the building without usable WiFi.
Worked example: when capacity beats coverage
A 500-person public event in a 1,200 m² hall. Coverage: 1,200 ÷ 900 = 1.3, so two access points would reach every corner. Capacity: about 500 phones ÷ 50 = 10 access points. Capacity wins by a long way.
Here the design changes shape as well as size. Ten access points in one hall need lower power, careful channel choices and placement close to where people stand, so each one serves its own patch of the crowd instead of talking over the others. That's the territory of WiFi for large crowds, and it's why big halls are planned from a floor plan rather than a formula.
What pushes the access point count up
Start from the arithmetic, then add for the things a calculator can't see.
Solid walls and separate rooms
Brick, concrete and fire-rated walls stop WiFi far more than open air. Breakout rooms, offices and green rooms usually need their own coverage.
Steel and racking
Steel frames, shelving and stock reflect and absorb signal. Long racked aisles behave like separate corridors and often need access points along them.
Extra levels
Mezzanines and upstairs offices rarely get usable signal from the floor below. Plan each level separately.
People themselves
Bodies absorb WiFi. A hall that tests well empty can lose coverage at the back once a crowd fills it.
Hot spots
Registration desks, stages, bars and stall rows concentrate devices. A zone with 150 devices needs three access points' worth of capacity on its own (150 ÷ 50 = 3).
Outdoor zones
Outdoor areas need weather-rated access points mounted with clear line of sight, and coverage is set by the site walk rather than floor area.
Questions people ask
How many WiFi access points do I need for 100 people?
For 100 public attendees with about one device each, plan two access points on capacity (100 ÷ 50). For 100 working people with laptops and phones, plan 150–200 devices and four access points (200 ÷ 50). Then check coverage by dividing the floor area by about 900 m², and use whichever count is higher.
How many devices can one access point handle?
As a starting point, plan about 50 devices per access point, a figure consistent with published high-density WiFi design guidance. An access point can technically connect more, but each extra device gets a smaller share of airtime, so performance drops in crowded spaces. Treat 50 as a planning number and confirm it on site.
How many access points do I need for 500 people?
For 500 public attendees with about one device each, plan about 10 access points on capacity (500 ÷ 50). If they're working people or exhibitors with 1.5–2 devices each, that's 750–1,000 devices and 15–20 access points. A crowd that size also needs channel planning and careful placement, not just a count.
How much area does one WiFi access point cover?
Our planning assumption is roughly one access point per 900 m² of open floor. Walls, steel structures, racking, mezzanines and extra levels reduce that, sometimes a lot. Outdoors, coverage depends on line of sight and mounting height. Use the area figure for a first estimate, then confirm with a site walk or floor-plan review.
Does a mesh node count as an access point?
Yes. A mesh node is an access point that links back to the network wirelessly instead of by cable, and it counts towards both capacity and coverage. Part of its radio capacity carries traffic between nodes, so cabled access points usually serve dense crowds better. Our guide to mesh vs wired access points explains the trade-off.
Can I just use one powerful router instead of several access points?
Not for most events. A single router, however powerful, is still one radio position with one share of airtime. It can't cover a large or walled space, and it can't serve hundreds of devices well. More power mostly helps devices hear the router, not the router hear the devices. Several well-placed access points do both.
Sources
Planning figures on this page are starting points. Every network is confirmed against the actual site.
