802.11ac (Wi-Fi 5): Speed, Range & Wi-Fi 6 Compared

802.11ac, retroactively branded WiFi 5, was ratified in 2013 and became the dominant wireless standard for roughly seven years. It operates only on 5 GHz, a dual band 802.11ac router falls back to 802.11n on the 2.4 GHz band.

It remains extremely common. Most devices bought between 2014 and 2020 are WiFi 5, and for a household internet connection under a few hundred megabits it is still entirely adequate.

What It Changed

Three of these carry most of the improvement: wider channels (80 MHz is four times 20 MHz), denser modulation (256-QAM), and more spatial streams. Multiply them together and the headline figures follow.

Wave 1 vs Wave 2

802.11ac shipped in two phases, and the distinction still matters when buying used or budget hardware:

MU-MIMO is the meaningful difference. Without it, an access point serves one client at a time, everyone else waits. With it, the AP transmits to several clients simultaneously using spatial separation. In a busy household that produces a real improvement in consistency, not just peak speed.

The caveat, and it is a significant one: 802.11ac MU-MIMO is downlink only. Uploads from clients to the AP still queue one at a time. WiFi 6 added uplink MU-MIMO.

Realistic Speeds

Advertised link rates and actual throughput are far apart, for reasons that are structural rather than a fault:

Roughly half the link rate is normal. WiFi is half duplex on a shared medium, with acknowledgements, contention windows, beacons and management frames all consuming airtime. Most phones and laptops are 2×2 anyway, so 867 Mbps negotiated and ~400 Mbps achieved is the common real-world case.

“AC1900” on a box means 600 Mbps of 2.4 GHz plus 1,300 Mbps of 5 GHz added together. No single device ever sees the combined figure.

Channel Width, the Setting That Matters Most

80 MHz is the right default. 160 MHz doubles theoretical throughput but requires DFS channels, which the AP must vacate for a minute whenever it detects radar, dropping every client. In a dense apartment building, 160 MHz also means you are occupying a large slice of spectrum your neighbours need, and the interference cuts both ways.

Beamforming and Its Limits

802.11ac standardised explicit beamforming: the AP and client exchange channel information, and the AP shapes its transmission to focus energy toward that client rather than radiating equally in all directions.

It genuinely improves signal quality at range, but only when both ends support it, and only where the AP has more antennas than the client. It is not a substitute for placing an access point closer to where coverage is needed.

WiFi 5 vs WiFi 6, Should You Upgrade?

OFDMA is the reason to upgrade, not the speed figures. It lets one transmission carry data for several clients at once by dividing the channel into sub-carriers. On a network with thirty devices, phones, TVs, sensors, plugs, most sending small amounts of data, this removes an enormous amount of queuing overhead. The improvement shows up as lower latency and better consistency, not a higher speed test number.

Upgrade if

• You have 25 or more connected devices.
• Several people stream or video call simultaneously.
• Your internet connection exceeds ~500 Mbps and WiFi is the bottleneck.
• Many battery-powered IoT devices would benefit from Target Wake Time.
• You live somewhere dense enough that BSS colouring helps.

Do not bother if

• Your connection is under 200 Mbps, WiFi 5 already exceeds it.
• You have few devices and no complaints.
• All your client devices are WiFi 5 anyway. The router cannot use features the clients lack.
• Your actual problem is coverage. Buy an access point, not a faster router.

That last point is worth emphasising, a newer standard does not increase range. See 2.4 GHz vs 5 GHz for why, and dual band routers for how the bands divide the work.

Frequently Asked Questions

Is 802.11ac the same as WiFi 5?

Yes. The WiFi Alliance introduced simplified names in 2018 and applied them retroactively, 802.11ac became WiFi 5, 802.11n became WiFi 4.

Does 802.11ac work on 2.4 GHz?

No, it is 5 GHz only. A dual band 802.11ac router runs 802.11n on its 2.4 GHz radio.

Why is my 802.11ac WiFi slower than advertised?

Advertised figures add both bands together and assume ideal conditions with the maximum stream count. Realistic throughput is roughly half the negotiated link rate, and most client devices are 2×2 rather than 4×4.

Is 802.11ac still good enough?

For most homes, yes. A 2×2 client at 80 MHz delivers around 400 Mbps of real throughput, which exceeds the majority of internet connections. Upgrade for device density, not raw speed.

What is MU-MIMO and does it help?

It lets the access point transmit to several clients at once instead of serving them in turn. In 802.11ac it is downlink only, and it requires client support. It helps in busy households and does nothing with one active device.

Should I enable 160 MHz channels?

Only with a clean RF environment and a genuine need. 160 MHz requires DFS channels, which drop the network briefly when radar is detected, and it is far more sensitive to interference. 80 MHz is the better default.