Wireless LAN (WLAN) channels are frequently accessed using IEEE 802.11 protocols. The 802.11 standard provides several radio frequency bands for use in Wi-Fi communications, each divided into a multitude of frequency channels numbered at 5 MHz spacing (except in the 45/60 GHz band, where they are 0.54/1.08/2.16 GHz apart) between the centre frequency of the channel. The standards allow for channels to be bonded together into wider channels for faster throughput.

860/900 MHz (802.11ah)

802.11ah operates in sub-gigahertz unlicensed bands. There are two main bands in use, with Europe mainly using 860 MHz, and the rest of the world mostly using 900 MHz.

860 MHz

indexIEEE 802.11-2024, table E-5. (MHz) Frequencyrange(MHz) Europe Singapore Rest of world 1MHz 2MHz 1 863.5 863–864 rowspan=5 rowspan=3 rowspan=6 3 864.5 864–865 5 865.5 865–866 7 866.5 866–867 rowspan=3 9 867.5 867–868 11 868.5 868–869

900 MHz

Each world region supports different sub-bands, and the channel numbers depend on the starting frequency on the sub-band it belongs to. Therefore there is no global channel numbering plan, and the channel numbers are incompatible between world regions (and even between sub-bands of a same world region). However, for the purposes of illustration, the following table lists all the worldwide permitted frequencies with the channel numbers assigned to the region with the largest number of permitted frequencies, the United States.

indexIEEE 802.11-2024, table E-5, for United States region. (MHz) Frequencyrange(MHz) AustraliaNew Zealand Europe Japan Korea Singapore Taiwan UnitedStates Rest ofworld 1MHz 2MHz 4MHz 8MHz 16MHz 1 902.5 902–903 rowspan=13 rowspan=15 rowspan=19 rowspan=16 rowspan=15 rowspan=18 rowspan=26 rowspan=29 3 903.5 903–904 5 8 12 20 904.5 904–905 7 905.5 905–906 9 906.5 906–907 11 907.5 907–908 13 16 908.5 908–909 15 909.5 909–910 17 910.5 910–911 19 911.5 911–912 21 24 28 912.5 912–913 23 913.5 913–914 25 914.5 914–915 27 915.5 915–916 rowspan=13 29 32 916.5 916–917 31 917.5 917–918 rowspan=3 rowspan=8 33 918.5 918–919 rowspan=6 35 919.5 919–920 37 40 44 920.5 920–921 rowspan=11 rowspan=5 39 921.5 921–922 rowspan=7 41 922.5 922–923 43 923.5 923–924 45 48 924.5 924–925 rowspan=3 47 925.5 925–926 rowspan=6 rowspan=6 49 926.5 926–927 51 52 927.5 927–928 rowspan=4 53 928.5 928–929 rowspan=3 rowspan=3 rowspan=3 55 56 929.5 929–930 57 930.5 930–931 1MHz 2MHz 4MHz 8MHz 16MHz (MHz) Frequencyrange(MHz) AustraliaNew Zealand Europe Japan Korea Singapore Taiwan UnitedStates Rest ofworld Notes:

Indonesia permits use in the 920–923 MHz band, however only with 250 kHz channels, below the minimum 1 MHz required for 802.11ah.

2.4 GHz (802.11b/g/n/ax/be/bn)

14 channels are designated in the 2.4 GHz range, spaced 5 MHz apart from each other except for a 12 MHz space before channel 14. The abbreviation F0 designates each channel's fundamental frequency.

F0(MHz) DSSS OFDM Most ofworld NorthAmericaIEEE 802.11-2007 — Table 18-9 Japan Frequencyrange(MHz) Channel22 MHz Frequencyrange(MHz) Channel20 MHz 40 MHz 1 2412 2401–2423 1 2  3 rowspan=2 2402–2422 1 2 3 rowspan=2 rowspan=3 rowspan=4 rowspan=5 rowspan=13 rowspan=11 rowspan=13 2 2417 2406–2428 4 2407–2427 4 3 2422 2411–2433 5 2412–2432 5 4 2427 2416–2438 6 2417–2437 6 5 2432 2421–2443 7 2422–2442 7 6 2437 2426–2448 8 2427–2447 8 7 2442 2431–2453 9 2432–2452 9 8 2447 2436–2458 10 2437–2457 10 rowspan=6 9 2452 2441–2463 11 2442–2462 11 rowspan=5 10 2457 2446–2468 12 2447–2467 12 rowspan=4 11 2462 2451–2473 13  2452–2472 13 rowspan=3 12 2467 2456–2478 rowspan=3 2457–2477 rowspan=2 rowspan=2 rowspan=2 13 2472 2461–2483 rowspan=2 2462–2482 14 2484 2474–2494 14 colspan=13 Notes:

In the 2.4 GHz bands bonded 40 MHz channels are uniquely named by the primary and secondary 20 MHz channels, e.g. 9+13. In the 5 GHz bands they are denoted by the center of the wider band and the primary 20 MHz channel e.g. 42

In the US, 802.11 operation on channels 12 and 13 is allowed under low-power conditions. The 2.4 GHz Part 15 band in the US allows spread-spectrum operation as long as the 50 dB bandwidth of the signal is within the range of 2,400–2,483.5 MHz, which fully encompasses channels 1 through 13. A Federal Communications Commission (FCC) document clarifies that only channel 14 is forbidden and that low-power transmitters with low-gain antennas may operate legally in channels 12 and 13. Channels 12 and 13 are nevertheless not normally used in order to avoid any potential interference in the adjacent restricted frequency band, 2,483.5–2,500 MHz, which is subject to strict emission limits set out in 47 CFR § 15.205. Per recent FCC Order 16–181, "an authorized access point device can only operate in the band when it is operating under the control of a Globalstar Network Operating Center and that a client device can only operate in the band when it is operating under the control of an authorized access point"

Channel 14 is valid only for DSSS and CCK modes (Clause 18 a.k.a. 802.11b) in Japan. OFDM (i.e., 802.11g) may not be used. (IEEE 802.11-2007 § 19.4.2)

Nations apply their own RF emission regulations to the allowable channels, allowed users and maximum power levels within these frequency ranges. Network operators should consult their local authorities as these regulations may be out of date as they are subject to change at any time. Most of the world will allow the first thirteen channels in the spectrum.

Interference happens when two networks try to operate in the same band, or when their bands overlap. The two modulation methods used have different characteristics of band usage and therefore occupy different widths: The DSSS method used by legacy 802.11 and 802.11b (and the 11b-compatible rates of 11 g) occupies 22 MHz of bandwidth. This is from the 11 MHz chip rate used by the coding system. No guard band is prescribed; the channel definition provides 3 MHz between 1, 6, and 11. The OFDM method used by 802.11g and 802.11n occupies a bandwidth of 16.25 MHz. The nameplate bandwidth is set to be 20 MHz, rounding up to a multiple of channel width and providing some guard band for signal to attenuate along the edge of the band. This guardband is mainly used to accommodate older routers with modem chipsets prone to full channel occupancy, as most modern Wi‑Fi routers are not prone to excessive channel occupancy.

While overlapping frequencies can be configured at a location and will usually work, it can cause interference resulting in slowdowns, sometimes severe, particularly in heavy use. Certain subsets of frequencies can be used simultaneously at any one location without interference (see diagrams for typical allocations). The consideration of spacing stems from both the basic bandwidth occupation (described above), which depends on the protocol, and from attenuation of interfering signals over distance. In the worst case, using every fourth or fifth channel by leaving three or four channels clear between used channels causes minimal interference, and narrower spacing still can be used at further distances. The "interference" is usually not actual bit-errors, but the wireless transmitters making space for each other. Interference resulting in bit-error is rare. The requirement of the standard is for a transmitter to yield when it decodes another at a level of 3 dB above the noise floor, or when the non-decoded noise level is higher than a threshold Pth which, for Wi-Fi 5 and earlier, is between -76 and -80 dBm.

As shown in the diagram, bonding two 20 MHz channels to form a 40 MHz channel is permitted in the 2.4 GHz bands. These are generally referred to by the centres of the primary 20 MHz channel and the adjacent secondary 20 MHz channel (e.g. 1+5, 9+13, 13–9, 5–1). The primary 20 MHz channel is used for signalling and backwards compatibility, the secondary is only used when sending data at full speed.

3.65 GHz (802.11y) Except where noted, all information taken from Annex J of IEEE 802.11y-2008

This range is documented as only being allowed as a licensed band in the United States. However, not in the original specification, under newer frequency allocations from the FCC, it falls under the Citizens Broadband Radio Service band. This allows for unlicensed use, under Tier 3 GAA rules, provided that the user doesn't cause harmful interference to Incumbent Access users or Priority Access Licensees and accepts all interference from these users, and also follows all the technical requirements in CFR 47 Part 96 Subpart E.

A 40 MHz band is available from 3655 to 3695 MHz. It may be divided into eight 5 MHz channels, four 10 MHz channels, or two 20 MHz channels.

The division into 5 MHz channels consumes all eight possible channel numbers, and so (unlike other bands) it is not possible to infer the width of a channel from its number. Instead each wider channel shares its channel number with the 5 MHz channel just above its mid frequency: channel 132 can be either 3660-3665 or 3655-3665; channel 133 can be either 3665-3670 or 3655-3675; and so on.

Channel Span 5 MHz 10 MHz 20 MHz 131 3655–3660(F0=3657.5) 3655–3665(F0=3660) 3655–3675(F0=3665) 132 3660–3665(F0=3662.5) 133 3665–3670(F0=3667.5) 3665–3675(F0=3670) 134 3670–3675(F0=3672.5) 135 3675–3680(F0=3677.5) 3675–3685(F0=3680) 3675–3695(F0=3685) 136 3680–3685(F0=3682.5) 137 3685–3690(F0=3687.5) 3685–3695(F0=3690) 138 3690–3695(F0=3692.5)

4.9–5.0 GHz (802.11j) WLAN

Channel Centerfrequency(MHz) Frequencyrange(MHz) Channel Japan UnitedStates 10MHz 20MHz 40MHz 184 4920 4910–4930 183, 184, 185 184 184+188188-184 rowspan=4 rowspan=4 188 4940 4930–4950 187, 188, 189 188 192 4960 4950–4970 rowspan=2 192 192+196196-192 196 4980 4970–4990 196 (191) 4955 4945–4965 11, 13, 15 21 rowspan=2 rowspan=2 (195) 4975 4965–4985 15, 17, 19 25 8 5040 5030–5050 7, 8, 9 8 rowspan=3 rowspan=3 12 5060 5050–5070 11, — 12 16 5080 5070–5090 16 In Japan since 2002, 80 MHz of spectrum from 4910 to 4990 MHz has been available for both indoor and outdoor use, once registered.

Until 2017, an additional 60 MHz of spectrum from 5030 to 5090 MHz was available for registered use, however it has since been re-purposed and can no longer be used.

50 MHz of spectrum from 4940 to 4990 MHz (WLAN channels 20–26) are in use by public safety entities in the United States. Within this spectrum there are two non-overlapping channels allocated, each 20 MHz wide. The most commonly used channels are 22 and 24.

5 GHz (802.11a/h/n/ac/ax/be/bn)

20 MHz (MHz) Frequencyrange(MHz) index US FCCU-NII band(s) Australia UnitedStates Canada UnitedKingdom Europe Russia Japan India Singa-pore Hong Kong SAR of thePRC China IsraelIsrael: Korea Turkey South Africa Brazil Taiwan NewZealand Bahrain Vietnam Indonesia Philippines 80MHz 160MHz 32 5160 5150–5170 U-NII-1 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=10 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=4 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=10 rowspan=10 36 5180 5170–5190 42 50 rowspan=8 40 5200 5190–5210 44 5220 5210–5230 48 5240 5230–5250 52 5260 5250–5270 58 U-NII-2A rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=4 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 rowspan=5 56 5280 5270–5290 60 5300 5290–5310 64 5320 5310–5330 68 5340 5330–5350 rowspan=2 rowspan=4 rowspan=8 style="border-bottom: 0px black" 72 5360 5350–5370 U-NII-2B rowspan=6 colspan=22 76 5380 5370–5390 rowspan=2 80 5400 5390–5410 84 5420 5410–5430 rowspan=2 rowspan=4 88 5440 5430–5450 92 5460 5450–5470 rowspan=2 96 5480 5470–5490