CompTIA A+ | Wireless Standards

802.11a

5 GHz, up to 54 Mbps. Early standard.

802.11b

2.4 GHz, up to 11 Mbps. Early standard, the slowest.

802.11g

2.4 GHz, up to 54 Mbps. Backward compatible with 802.11b.

802.11n (Wi-Fi 4)

2.4 GHz and 5 GHz, up to 600 Mbps. Introduced MIMO.

802.11ac (Wi-Fi 5)

5 GHz only, up to several Gbps (about 3.5-6.9 Gbps). Added MU-MIMO.

802.11ax (Wi-Fi 6)

2.4 GHz and 5 GHz, up to about 9.6 Gbps. Better performance in crowded areas.

Wi-Fi 6E

802.11ax extended to also use the 6 GHz band.

802.11be (Wi-Fi 7)

2.4, 5, and 6 GHz. Newest standard, with wider channels (up to 320 MHz) and even higher speeds.

Which 802.11 standards use ONLY 2.4 GHz?

802.11b and 802.11g

Which 802.11 standards use ONLY 5 GHz?

802.11a and 802.11ac

Which standards use BOTH 2.4 and 5 GHz?

802.11n and 802.11ax (and 802.11be)

Which standards can use 6 GHz?

Wi-Fi 6E (802.11ax) and Wi-Fi 7 (802.11be)

Which standards max out at 54 Mbps?

802.11a and 802.11g

Slowest 802.11 standard

802.11b (11 Mbps)

MIMO

Multiple Input, Multiple Output. Uses multiple antennas to send and receive more data at once. Introduced with 802.11n.

MU-MIMO

Multi-User MIMO. Lets an access point send data to multiple devices at the same time. Introduced with 802.11ac.

Wi-Fi 4 / 5 / 6 / 7

Wi-Fi 4 = 802.11n, Wi-Fi 5 = 802.11ac, Wi-Fi 6 = 802.11ax, Wi-Fi 7 = 802.11be

Backward compatibility

Newer Wi-Fi standards still work with older devices on the same band, but older devices connect at their own slower speed.

A user has an old 802.11g laptop. Can it connect to a 5 GHz-only network?

No. 802.11g only supports 2.4 GHz.

A company with a crowded office wants the best wireless performance for many devices. Which standard?

802.11ax (Wi-Fi 6) or newer.

A client wants to use the 6 GHz band. What do both the router and devices need to support?

Wi-Fi 6E or Wi-Fi 7.

An 802.11n network supports which bands?

Both 2.4 GHz and 5 GHz.