WiFi Capacity
Calculate the number of concurrent devices a WiFi network can support at target throughput.
About WiFi Capacity
Aggregate WiFi capacity is the product of how many channels are used, how wide each channel is, how efficiently the modulation and coding scheme packs bits into each Hz of spectrum, and how many spatial streams MIMO antennas can carry in parallel. Doubling channel bandwidth, spectral efficiency, or spatial streams each roughly doubles capacity, which is why 802.11ax (WiFi 6) achieves far higher throughput than 802.11n primarily through wider channels, denser modulation (1024-QAM), and more spatial streams rather than a faster underlying radio.
Formula
Aggregate capacity
capacity = channels × channel_bandwidth × spectral_efficiency × MIMO_streams
- n_{ch}
- Number of channels in use
- B_{ch}
- Channel bandwidth in Hz
- \eta
- Spectral efficiency in bits/second/Hz
- N_{ss}
- Number of MIMO spatial streams
Worked example
With the default values below, WiFi Capacity returns Total Capacity of 1,376.00. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Number of Channelsminimum 1
- 1
- Channel Bandwidthone of 20 MHz, 40 MHz, 80 MHz, 160 MHz
- 80 MHz
- Spectral Efficiencyminimum 0.1 bps/Hz
- 8.6 bps/Hz
- MIMO Spatial Streamsaccepts 1–8
- 2
Results
- Total Capacity
- 1,376.00 Mbps
- Total Capacity
- 1.376 Gbps
- Capacity per Channel
- 1,376.00 Mbps
Step by step
- 1Values used
- 2Aggregate capacity
- 3Total Capacity= 1,376.00 Mbps
- 4Total Capacity= 1.376 Gbps
- 5Capacity per Channel= 1,376.00 Mbps
Assumptions and limits
- The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
Why does channel bandwidth matter so much for capacity?
Capacity scales linearly with channel bandwidth because a wider channel carries proportionally more subcarriers (in OFDM/OFDMA systems), each capable of carrying the same bits/Hz — doubling bandwidth from 40 MHz to 80 MHz roughly doubles raw capacity, all else equal.
What is spectral efficiency and why does it vary?
Spectral efficiency is how many bits per second a system can pack into each Hz of bandwidth, determined by the modulation order (QPSK, 64-QAM, 1024-QAM, etc.) and coding rate. Denser modulation packs more bits per symbol but requires a cleaner signal (higher SNR) to be decoded reliably.
How much does MIMO improve capacity?
Each additional spatial stream can roughly add another multiple of the single-stream capacity, since MIMO transmits independent data streams simultaneously over multiple antennas exploiting multipath — though real-world gains depend on antenna count, spacing, and channel conditions.
Is this the throughput a single client will see?
No — this is aggregate cell/AP capacity shared across all associated clients and channels. An individual client's achievable throughput depends on its own supported streams/bandwidth, its distance-driven SNR, and contention with other devices on the same channel.