5 GHz Channel Planner
Count the non-overlapping 5 GHz channels available at your chosen width with or without DFS, and check the reuse it allows.
About 5 GHz Channel Planner
Excluding DFS leaves only UNII-1 (36–48) and UNII-3 (149–165), which is nine 20 MHz channels and no 160 MHz channel at all. Adding the UNII-2 and UNII-2e radar bands roughly triples the count, at the cost of radar-detection channel changes. Channel reuse is what determines whether adjacent APs cooperate or compete, and avoiding DFS to dodge radar events is exactly what starves a dense floor of spectrum.
Formula
5 GHz Channel
channels = usable 5 GHz spectrum ÷ channel width, counted separately for the DFS and non-DFS sets; radios per channel = radios ÷ channels.
- withDfs
- 25/12/6/2 channels at 20/40/80/160 MHz with DFS
- withoutDfs
- 9/4/2/0 channels using only UNII-1 and UNII-3
Worked example
With the default values below, 5 GHz Channel Planner returns Non-Overlapping Channels of 12. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Channel widthone of 20 MHz, 40 MHz, 80 MHz, 160 MHz
- 40 MHz
- DFS (UNII-2 / UNII-2e) channels permitted
- Yes
- 5 GHz radios in the coverage areaaccepts 1–1,000 radios
- 24 radios
Results
- Non-Overlapping Channels
- 12
- Radios Sharing Each Channel
- 2.00
- Co-Channel Neighbours per Radio
- 1.00
- Spectrum in Use
- 480 MHz
- Assessment
- Acceptable reuse for a typical enterprise floor
Step by step
- 1Values used
- 25 GHz Channel
- 3Non-Overlapping Channels= 12
- 4Radios Sharing Each Channel= 2.00
- 5Co-Channel Neighbours per Radio= 1.00
- 6Spectrum in Use= 480 MHz
- 7Assessment= Acceptable reuse for a typical enterprise floor
Assumptions and limits
- The result is derived only from the 3 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 2 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
How is 5 GHz Channel calculated?
channels = usable 5 GHz spectrum ÷ channel width, counted separately for the DFS and non-DFS sets; radios per channel = radios ÷ channels. Excluding DFS leaves only UNII-1 (36–48) and UNII-3 (149–165), which is nine 20 MHz channels and no 160 MHz channel at all. Adding the UNII-2 and UNII-2e radar bands roughly triples the count, at the cost of radar-detection channel changes.
Why does 5 GHz Channel matter?
Channel reuse is what determines whether adjacent APs cooperate or compete, and avoiding DFS to dodge radar events is exactly what starves a dense floor of spectrum.
What values do I need to enter?
This calculator takes 3 inputs: Channel width, DFS (UNII-2 / UNII-2e) channels permitted, 5 GHz radios in the coverage area. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.