Wi-Fi 7 vs Wi-Fi 6: What Actually Changes

Wi-Fi 7, formally IEEE 802.11be, keeps the same three radio bands as Wi-Fi 6 and 6E but changes how much of them a device can use and how it uses them. The main differences are wider channels of up to 320 MHz, a denser signal encoding called 4096-QAM, and multi-link operation, which lets one device use more than one connection at the same time. The headline speeds are theoretical peaks, and real-world results depend on many things.

The three biggest changes

The table-style comparison below follows the Devopedia entry on 802.11be, which compares Wi-Fi 7 with Wi-Fi 6 and 6E:

• Channel width: up to 160 MHz in Wi-Fi 6, up to 320 MHz in Wi-Fi 7, and the 320 MHz option works only in the 6 GHz band.
• Signal encoding: 1024-QAM in Wi-Fi 6, which carries 10 bits per symbol, against 4096-QAM in Wi-Fi 7, which carries 12 bits per symbol.
• Multi-link operation (MLO): not available in Wi-Fi 6, introduced in Wi-Fi 7.
• Theoretical peak rate: about 9.6 Gbps for Wi-Fi 6 and 46 Gbps for Wi-Fi 7.

The Wi-Fi Alliance, the industry group that certifies Wi-Fi products, lists the same headline features for Wi-Fi CERTIFIED 7: 320 MHz channels in 6 GHz, multi-link operation, 4K QAM, 512 compressed block acknowledgement and multiple resource units for a single device.

Wider channels

A channel is a slice of radio spectrum, and a wider slice can carry more data, much like a wider road. Devopedia explains that the 2.4 GHz band supports only 20 and 40 MHz channels, the 5 and 6 GHz bands support 80 and 160 MHz, and 320 MHz is possible only in 6 GHz, where there is room for 60 channels of 20 MHz. The Wi-Fi Alliance says 320 MHz channels double Wi-Fi 6's throughput for multigigabit device speeds.

There is a practical limit. The 6 GHz band is not available to Wi-Fi in the same way everywhere. Devopedia reports that in December 2023 the World Radiocommunication Conference set aside the 6.425 to 7.125 GHz range for licensed 5G in some regions, so 6 GHz will not be available for Wi-Fi 7 worldwide. The channel width you can get depends on the rules in your country.

A denser signal: 4096-QAM

QAM stands for quadrature amplitude modulation, a way of encoding bits by varying the signal in two ways at once. More points on the pattern means more bits per symbol but also less tolerance for noise. Moving from 1024-QAM to 4096-QAM raises the bits per symbol from 10 to 12. The Wi-Fi Alliance says this gives about 20% higher transmission rates than Wi-Fi 6.

The gain has a catch. Devopedia notes that 4096-QAM helps mainly on clear, line-of-sight links with beamforming reaching about 30 dB signal quality. A device far away or behind walls will not see the benefit.

Multi-link operation

Earlier Wi-Fi generations connect a device over one band at a time. Multi-link operation lets a Wi-Fi 7 device and access point communicate over several links, for example 5 GHz and 6 GHz together. The Wi-Fi Alliance says this balances traffic across links for higher throughput and better reliability. If one link is congested, traffic can move to another.

Devopedia lists several device types, including multi-link single radio (MLSR), enhanced MLSR, multi-link multi-radio (MLMR) and enhanced MLMR. They differ in how many radios a device has and whether it can send and receive on different links at once. A phone with one radio and a router with several will therefore not get identical benefits.

Smarter use of spectrum

Wi-Fi 7 adds preamble puncturing. If something interferes with one 20 MHz piece of a wide channel, the system can skip that piece and use the rest. Devopedia gives the example of using 300 of 320 MHz, where Wi-Fi 6 would fall back to 160 MHz. Wi-Fi 7 can also give one device several resource units at once, meaning more flexible slices of the channel.

Peak speed versus real speed

The 46 Gbps figure assumes 16 spatial streams, the widest channel and the best encoding. Devopedia shows the calculation and notes that, as of January 2024, no chipset had reached it, with Qualcomm's Networking Pro 1620 reaching 33 Gbps. Consumer devices commonly have fewer streams, so peak numbers on a box are an upper limit, not what you will see when downloading a file.

Timeline

• March 2023: IEEE draft 2.0 of 802.11be published.
• December 2023: draft 4.0 followed, according to Devopedia.
• January 2024: Wi-Fi CERTIFIED 7 launched, per Devopedia.
• The Wi-Fi Alliance page cites ABI Research as projecting 1.4 billion Wi-Fi 7 chipset shipments in 2026.

In short, Wi-Fi 7 is an evolution of Wi-Fi 6E rather than a break from it. It is backward compatible, so older devices still connect, but the main gains need Wi-Fi 7 on both the router and the device, and in the case of 320 MHz channels, a 6 GHz band that is open in your region. This article is general information, and figures are as published by the sources named.

Sources

• IEEE 802.11be, Devopedia
• Wi-Fi CERTIFIED 7, Wi-Fi Alliance