WiFi Channel Calculator
Best WiFi channels and widths for 2.4, 5, and 6 GHz.
What it does
WiFi channels overlap like lanes painted too narrow. On 2.4 GHz each 20 MHz signal spreads ~22 MHz across 5 MHz channel steps, so neighbors bleed into each other and only channels 1, 6, and 11 stay mutually clear. Picking any other channel borrows interference from both sides.
The tool above plans all three bands. 2.4 GHz gives the 1/6/11 trio at 20 MHz. 5 GHz opens UNII-1 (36-48) and UNII-3 (149-165) with 20/40/80 MHz widths. 6 GHz adds 59 clean 20 MHz channels with 15 PSC scan channels from 5 to 229.
Regulators drew these maps. The FCC U-NII order sets 5 GHz bands to 5.85 GHz with DFS sharing in the middle, and its 6 GHz order opened 5925-7125 MHz for unlicensed use. The Wi-Fi Alliance confirms the US 6 GHz adoption behind the PSC scheme.
Width trades capacity against channel count. One 80 MHz channel (e.g. 42 over 36-48) quadruples speed but quarters choices, and on 2.4 GHz anything past 20 MHz jams neighbors outright. Match width to density: wide at home, narrow in offices.
How to use
- Pick the WiFi band.
- Read the channel set first.
- Read the width line.
- Read the count of clean choices.
- Repeat 1/6/11 across 2.4 GHz APs.
- Scan PSC on 6 GHz clients.
Formula
- band
- WiFi band selector: 2.4, 5, or 6 GHz.
- PSC
- Preferred Scanning Channels clients check first.
Band edges follow FCC rules (U-NII to 5.85 GHz, 6 GHz 5925-7125 MHz). PSC counts verified against vendor channel tables.
Worked example
Example: 2.4 GHz plan
Defaults: 2.4 GHz band.
- Input: 2.4 GHz band.
- Only 3 non-overlapping 20 MHz channels exist.
- Use 1, 6, or 11, repeating across APs.
- Keep 20 MHz width; wider hurts neighbors.
- Tool shows 1, 6, 11, 20 MHz only, 3 non-overlapping.
Reference table
| Band | Use | Width |
|---|---|---|
| 2.4 GHz | 1, 6, 11 | 20 MHz only |
| 5 GHz UNII-1 | 36, 40, 44, 48 | 20/40/80 MHz |
| 5 GHz UNII-3 | 149-165 | 20/40/80 MHz |
| 6 GHz | PSC 5-229 step 16 | 20 to 320 MHz |
Limits
- US rules only. EU/JP channel sets differ.
- Planning aid, not a site survey; walls vary.
- DFS radar vacate rules sit outside.
- Client support varies by band and width.
Common mistakes
- Picking 2.4 GHz channel 3 between 1 and 6.
- Running 40 MHz wide on crowded 2.4 GHz.
- Using DFS channels without radar behavior.
- Assuming more bars beat cleaner channels.
- Skipping a rescan after neighbor changes.
Try it yourself
Quick checks. Answers sit tucked under each question.
5 GHz home plan?
UNII-1 36, 40, 44, 48 or UNII-3 149-165 at 20/40/80 MHz. Skip DFS.
6 GHz scan channels?
15 PSC: 5, 21, 37 to 229. First center 5975, last 7095 MHz.
Questions
Which 2.4 GHz channels do I use?
1, 6, and 11 at 20 MHz. Each signal runs ~22 MHz wide on 5 MHz spacing, so only these three clear each other.
Which 5 GHz channels do I use?
UNII-1 (36-48) or UNII-3 (149-165) with 20, 40, or 80 MHz widths. Skip DFS UNII-2 channels at home.
What are 6 GHz PSC channels?
PSC channels every 16 from 5 to 229 (15 total): 5, 21, 37, up to 229. Clients scan these first.
How do 6 GHz channel numbers work?
Center math: 5950 + 5n MHz. Channel 5 sits at 5975, channel 229 at 7095.
Do wide channels reduce choices?
Yes. One 80 MHz channel bonds four 20 MHz ones (e.g. 42 covers 36-40-44-48). Fewer clean channels result.
What are the center formulas?
2.4 GHz: 2407 + 5n (ch 1 = 2412). 5 GHz: 5000 + 5n (ch 36 = 5180).
Sources
- FCC: U-NII 5 GHz Rules (bands to 5.85 GHz)
- FCC: 6 GHz VLP Order (5925-7125 MHz)
- Wi-Fi Alliance: 6 GHz Regulations Map