Looking to get Wi-Fi 6 explained adequately? You're at the right place!
Since first commercially viable in early 2019, the new Wi-Fi standard has proven to be confusing from the get-go. Among other things, it seems impossible to match a router's marketing specs and what it can realistically deliver. Hint: You can't.
I'll try to explain all about this new Wi-Fi standard in this post. By all, I mean just the parts that matter, not the technical details or the marketing hype. Already in the know? This post is a good refresher.
Dong's note: I first published this piece on January 10, 2019, and updated it on April 29, 2020, with additional relevant information, including a brief section on Wi-Fi 6E. Since then, it has had more minor updates with up-to-date information.
Wi-Fi 6 explained: What is it exactly?
It's a new and trendy name and a great idea, coined by the Wi-Fi Alliance in late 2018, for us to call what otherwise is known as the 802.11ax Wi-Fi standard.
The 6 designation is numerical — it's the 6th generation of Wi-Fi. For the same token, tracking backward, we have 802.11ac as Wi-Fi 5, 802.11n as Wi-Fi 4, and so on. There will be Wi-Fi 7 in the future.
The new naming convention goes back only to Wi-Fi 4 (802.11n) because previous standards are largely obsolete. In other words, don't bother with Wi-Fi 3, Wi-Fi 2, etc.
How fast is Wi-Fi 6?
Everybody wants to know how fast Wi-Fi 6 is, compared to Wi-Fi 5 and older.
As a result, the speeds — yes, it's plural — of Wi-Fi 6 have been a big hype. There's a large gap between the theoretical and the real ones.
The issue is figuring out the speed of Wi-Fi 6 can be challenging and confusing. There are just too many variants. That said, make sure you take your time in the next part.
Wi-Fi 6 equipment: Broadcasters vs. receiver and their number of streams
To know a Wi-Fi connection's real-world speed, we need a broadcaster (like a router) and a client (like a laptop). Both have to be of the same standard and performance tier, determined by the number of streams a single Wi-Fi band can handle.
Bands vs. Channels vs. Streams
Wi-Fi uses three frequency bands, including 2.4GHz, 5GHz, and 6GHz. The width of each band is measured in MHz — the wider the band, the more MHz it has.
The 6GHz band is the widest of the three and has 1200MHz in total width, ranging from 5.925GHz to 7.125GHz. Depending on the local regulations, only a portion or portions of this entire spectrum is available for Wi-Fi applications.
In real-world usage, each band is divided into multiple portions, called channels, of different widths. Depending on the Wi-Fi standards and hardware, a channel can be 20MHz, 40MHz, 80MHz, 160MHz, or 320MHz wide. The wider a channel is, the more bandwidth it has. Depending on the channel width, the number of channels in each Wi-Fi band varies, but there can be only so many.
The 6GHz band has enough space for three 320MHz channels or seven 160MHz channels.
Data moves in one channel of a particular band at a time, using streams, often dual-stream (2x2), three-stream (3x3), or quad-stream (4x4). The more streams, the more data can travel at a time.
Here's a crude analogy:
If a Wi-Fi band is a freeway, channels are lanes, and streams are vehicles (bicycles vs. cars vs. buses). On the same road, you can put multiple adjacent standard lanes (20MHz) into a larger one (40MHz, 80MHz, or higher) to accommodate oversized vehicles (higher number of streams) that carry more goods (data) per trip (connection).
A Wi-Fi connection generally occurs on a single channel (lane) of a single band (road) at a time. The actual data transmission is always that of the lowest denominator — a bicycle can carry just one person at a relatively slow speed, even when used on a super-wide lane of an open freeway.
If you use a sender and a receiver of two different speed grades, the connection speed is that of the slower one — the bottleneck.
Let's start with the sending end.
Wi-Fi 6 speed: On the broadcasting side
A Wi-Fi broadcaster (router or access point) emits wireless signals for clients to connect to. And there have been many Wi-Fi 6 broadcasters covering all different tiers of the new standard.
For example, you can find high-end Quad-stream (4x4) routers, such as the Netgear RAX200, the Asus RT-AX89X, the TP-Link AX6000, and many more. There are also mid-tier Dual-stream (2x2) broadcasters, like the Netgear RAX40, TP-Link Archer AX3000, or Asus RT-AX3000.
The point is: There are many (fast) options on the broadcasting end.
Wi-Fi 6 speed: On the receiving end
On the receiving end, we've had only dual-stream (2x2) devices — like the Intel AX200 adapter card. And it will be a long time before you can find 3x3, 4x4, or faster Wi-Fi 6 clients, if ever.
That's because 2x2 is already plenty fast. Most importantly, this tier has the right balance of wireless speeds and energy consumption and is the most suitable for mobile devices.
But that's OK. It never hurts to have a super-fast broadcaster anyway, even when we only have mid-tier clients. But how fast is fast?
A 4x4 Wi-Fi router can handle two 2x2 clients at full speeds.
The new base Wi-Fi speed
Generally, on the 5GHz frequency band, Wi-Fi 6 has a base speed of 1.2 Gbps (1200 Mbps) per stream. Hence, a 2x2 connection has a ceiling speed of 2.4 Gbps (2400Mbps), and a quad-stream (4x4) tops at a whopping 4.8 Gbps.
The 2.4GHz band of Wi-Fi 6 has a base speed of about 288Mbps per stream on paper and tends to be relatively slow in real life. Its real-world rate is about the same as Wi-Fi 4 — there's no 2.4GHz in Wi-Fi 5.
The 2.4GHz band of Wi-Fi 6 is generally considered a backup since it has relatively slow speed grades on paper and even more so in real-world rates.
The bottom line of Wi-Fi 6 speed in the best-case scenario
Since a network connection always has the speed of the slowest party involved, for now, and likely in the foreseeable future, Dual-stream (2x2) is the fastest connection we can get out of Wi-Fi 6 — we only have 2x2 clients, as mentioned above.
As a result, in the best-case scenario, we get the theoretical ceiling speed of 2.4Gbps (or 2400Mbps) out of Wi-Fi 6.
In the world of wireless data transmissions, the real-world sustained rates are always much lower than the theoretical ones. And that's acutely so in the case with Wi-Fi 6.
Intel calls its 2x2 AX200 chip "Gig+", meaning it can deliver real-world speed faster than Gigabit but slower than 2Gbps. And that's generally been the numbers I've gotten in my real-world testing.
Data transmission speeds in a nutshell
As you read this page, keep in mind that each character on the screen, including a space between two words, generally requires one byte of data.
The phrase "Dong Knows Tech," with no quotes, requires at least 15 bytes, and likely more since the formatting — such as capitalization and font — also needs extra storage space.
Byte -- often in thousands or kilobytes (kB), millions or megabytes (MB), and billions or gigabytes (GB) — is generally used to convey storage space. For data transmission, we use bits.
One byte equals eight bits.
One million (1,000,000) bits = 1 Megabit (Mb).
Megabits per second (Mbps) — the number of megabits being manipulated in one second — is the common unit for data transmission nowadays. Based on that, the following are common terms:
- Fast Ethernet: A connection standard that can deliver up to 100Mbps.
- Gigabit: That's short for Gigabit Ethernet (GbE) and generally means transmission speeds in Gigabit per second (Gbps). This is currently the most popular wired connection standard. 1Gbps = 1000Mbps.
- Gig+: A connection that's faster than 1Gbps but slower than 2Gbps. It often applies to 2x2 Wi-Fi 6/6E or Internet speeds.
- Multi-Gigabit: That's multiple Gigabits — a link that's 2Gbps or faster.
- Multi-Gig: A new BASE-T wired connection standard that delivers 2.5GbE, 5Gbe, or 10GbE over CAT5e (or a higher grade) network cables, depending on the devices involved, and is also backward compatible with Fast Ethernet and Gigabit.
In short, the current absolutely best Wi-Fi 6 connection sustains around 1.5Gbps (1500Mbps). But that's only on a good day. The 5GHz band is complicated.
Let's dig a bit more.
Wi-Fi 6 speeds and DFS channels: The devil is in the details
The rates mentioned above — 2.4 Gbps for a dual-stream and 4.8 Gbps for a quad-stream — only apply when the devices connect using the 160MHz channel width, which is the novelty of Wi-Fi 6.
However, most existing devices do not support this new channel width, nor do many Wi-Fi 6 ones.
The reasons? First, as the number suggests, this extensive channel encompasses multiple narrower ones. Consequently, there are only two 160MHz channels on the 5GHz band. Most importantly, both require the Dynamic Frequency Selection (DFS) spectrum.
Technically, we can get a completely clean (non-DFS) 160MHz channel out of the 5GHz frequency band if/when the 45 MHz of the 5.9GHz portion is opened up to Wi-Fi use. That remains to be seen.
DFS shares airspace with radar and always takes the back seat. Specifically, a Wi-Fi broadcaster automatically switches its DFS channels or moves to a narrower channel width when radar signals are present. Apart from causing brief disconnections now and then, using DFS can also be why some devices can't connect at top Wi-Fi speeds.
Many existing clients (Wi-Fi 5 and older) don't support DFS, though all Wi-Fi 6 ones do.
Wi-Fi 6: DFS, 160MHz channel width, and your patience
When customizing a Wi-Fi 6 broadcaster's Wi-Fi setting, you can't pick a 160MHz channel as a whole. Instead, you can only select a base channel (generally a 40MHz or 20MHz one). The hardware will automatically add adjacent extension channels on either side of the base to form a 160MHz channel.
When you force a router to use the DFS channels, such as when you set it to operate in the 160MHz channel width, it will take a longer time — between 1 and 10 minutes — to initiate its DFS-related 5GHz band. The exact wait time depends on your environment and equipment.
Consequently, you'll notice that your high-end Wi-Fi 6 router might take a long time to boot up or apply specific Wi-Fi settings, resulting in the band appearing unavailable — the 5GHz Wi-Fi network is not there, or you can't connect to it.
Keep this in mind when you're tweaking your network. Patience is a virtue.
In short, the 160MHz channel width is premium real estate that's generally not ideal for those close (within tens of miles) to an airport or a weather radar station — every big city has at least one of those.
160MHz vs. 160MHz (80+80) channels
To avoid DFS, some Wi-Fi chips have the 160MHz (80+80) mode by combining two non-contiguous 80MHz channels into a single one — like in the case of the Netgear RAX120.
The 160MHz (80+80) approach is a hack and doesn't deliver the same performance as a natural 160MHz channel. It hardly works in real-world testing and is considered abandoned, especially with the subsequent availability of the UNII-4 portion.
Wi-Fi 6’s true real-world speed (vs. Wi-Fi 5)
For backward compatibility, hardware constraint, and often stability, Wi-Fi 6 also uses narrower channels, including 80MHz, 40MHz, and 20MHz.
Many routers, such as the AmpliFi Alien, most canned mesh systems, and Wi-Fi 6 access points, don't even support the 160MHz channels, partly to avoid the need for DFS channels and the potential sporadic disconnections.
So, you should expect your Wi-Fi 6 router to use the 80MHz channel width and narrower ones most of the time.
In this case, the speed will reduce accordingly by a factor of two. For example, via an 80MHz channel, a 2x2 Wi-Fi 6 connection now caps at 1200Mbps or 600Mbps per stream. That's less than 50 percent faster than Wi-Fi 5's 433Mbps.
So, in reality, you should expect Wi-Fi 6 to reliably deliver about 50 percent improvement over Wi-Fi 5 in terms of sustained data rates in the same specs — 2x2 vs. 3x3 vs. 4x4, etc.
And no, Wi-Fi 6 is not necessarily always faster. Here's an interesting fact: Quad-stream (4x4) Wi-Fi 5 devices, which have a cap speed of 1733 Mbps at 80MHz, can deliver faster real-world speeds than 2x2 Wi-Fi 6 counterparts using the same channel width (1200Mbps).
And that proved to be the case in my testing. While Wi-Fi 6 is faster as a standard, it's not always so in real-world usage, which has lots of variations and nuances.
The marketing ploys
The lack of support for the 160MHz channel bandwidth is generally not necessarily good, but networking vendors have figured out a way to make it sound good.
Quite creatively, they call their 80MHz-at-best Wi-Fi 6 routers 8x8 (instead of 4x4). Because 8 x 600 = 4 x 1200. Got it? The problem is there are no 8x8 clients.
(Again, technically, things are more complicated than that. For example, if clients of different tiers all used the 80MHz channel width, these 8x8 routers might have some advantages since they are geared toward this configuration. Realistically, the Wi-Fi airspace is anything but conforming, and you always have clients using different channel widths.)
Another thing with Wi-Fi 6 is that we now have routers that use different Wi-Fi tiers and standards for each band. The Asus RT-AX92U, for example, is a tri-band Wi-Fi 6 router with one 2x2 2.4 GHz Wi-Fi 4 band, one 2x2 5 GHz Wi-Fi 5 band, and another 4x4 5 GHz Wi-Fi 6 band.
Networking vendors add all these bands' streams into a single (large) number for marketing purposes. Asus calls the RT-AX92U an 8-stream (8x8) router. Furthermore, they combine the bandwidth of all of the router's bands into a single (huge) number. As a result, you'll find AX6000, AX11000 routers, and so on.
That said, these numbers only mean the potentials collective bandwidth of a router when all of its bands are used. Since a Wi-Fi connection takes place on a single band at a time, the fastest band of a router determines its cap speed, not its bands or the total number of streams.
So, the Asus RT-AX92U mentioned above is a 4x4 Wi-Fi 6 router that can deliver up to 4.8 Gbps to a 4x4 client or 2.4 Gbps to a 2x2 client.
And that's only true when it works as a single router with a single client. That's because a Wi-Fi router shares its wireless bandwidth between connected clients.
Wi-Fi 6 speeds are a complicated matter
A router must have at least one multi-gig LAN port to deliver actual Wi-Fi 6 speeds. Otherwise, the Wi-Fi connection's real-world speed will cap at 1 Gbps, no matter how fast its wireless rate can be.
That's because, in a wireless-to-wireless connection, where you transfer data from one Wi-Fi device to another, the router shares its bandwidth accordingly. For example, when you copy data between two 2x2 (2.4 Gbps) Wi-Fi 6 devices using the same band, the speed between them will cap at just 1.2 Gbps.
So, a good Wi-Fi 6 router, strictly in terms of speeds, needs to have 4x4 specs (or higher) on a single band and a couple of multi-gig network ports. Most importantly, it needs to support the venerable 160MHz channel bandwidth.
And that brings us to a new and potentially exciting version of Wi-Fi 6, the Wi-Fi 6E.
Wi-Fi 6 speeds compared with older standards
and Theoretical Speed (in Mbps)
|Max Number Streams
Used in Clients
(max theoretical speed•)
|Single-stream or 1x1
|Quad-stream or 4x4
|Dual-stream or 2x2
|(85Mbps to 150Mbps)
• The absolute best theoretical speed of a real-world connection in an ideal connection before interference, signal degradation, and hardware incompatibility are taken into account. Among the mainstream standards, depending on the number of streams and channel width in use, this theoretical ceiling speed is lower, often by half. In any case, you need to discount this ceiling number by another 30% or 50% to get the real-world sustained rates.
•• The 5GHz band is split into two portions as sub-bands.
••• The 5GHz or 6GHz band is split into two portions as sub-bands.
Wi-Fi 6E: The answer to spectrum shortage
In early 2020, the Wi-Fi Alliance introduced the Wi-Fi 6E terminology to call Wi-Fi 6 devices capable of working on the new 6 GHz frequency band.
The purpose of Wi-Fi 6E is to address the spectrum shortage — you'll get more natural 160MHz channels out of the new frequency. But Wi-Fi 6E also has its issues as I detailed in this post.
Wi-Fi 6: Frequently asked questions
If the part above has given you a headache, yet, you still can wrap your head around what Wi-Fi 6 entails, my answer to the common questions about the standard below will help.
Will I be able to download a movie much faster with Wi-Fi 6?
Not necessarily! Here's why: Downloading a movie (or Netflix streaming, for that matter) depends on the Internet speed, which has little to do with Wi-Fi. They are two different things.
Wi-Fi is the alternative to network cables — it allows for a local network without wires. So, the increased speed of Wi-Fi 6 (or any Wi-Fi standard for that matter) is only meaningful locally, within your home or office.
In other words, assuming all your devices are Wi-Fi 6-enabled, you'll be able to print, perform network Time Machine backups, stream from a local NAS server, etc., much faster.
As for the Internet, most residential broadband services offer speeds significantly below that of Wi-Fi 5, which is already plenty fast. Consequently, if you use Wi-Fi 6, you'll experience no improvement in Internet access.
In networking, the final speed of a connection is always that of the slowest party involved. Right now, in most cases, the Internet is that party.
It'll be a few years or even a decade — when 5G cellular and Gigabit-class broadband are ubiquitous — before we need Wi-Fi 6 to deliver the Internet in full. But then, remember that your client needs to support the same Wi-Fi standard to get the fast speed out of a router.
Wi-Fi 6: Better efficiency with OFDMA and TWT
Wi-Fi 6 features orthogonal frequency-division multiple access (OFDMA), on top of the fact it has MU-MIMO by default.
In a nutshell, Wi-Fi 6 can slice its wireless signals into many perfectly sized chunks and, therefore, can simultaneously feed more clients of different Wi-Fi specs and keep them all happy — without slowing down, that is.
Potentially, Wi-Fi 6 can maintain fast individual connections even in crowded air spaces with many clients.
MIMO vs. MU-MIMO vs. ODFMA
It's hard to explain MIMO, MU-MIMO, and ODFMA without invoking technical jargon. That said, let's go with this analogy. Imagine a Wi-Fi band as a freeway, channels would be lanes of different sizes (MHz), and we'd have the following:
- MIMO is when you use multiple trucks of the same size simultaneously. That's more efficient than using just one truck that has to go back and forth, but not great since the trucks can be too large for a certain load.
- MU-MIMO is when you use multiple vehicles of different types depending on the load's size or type. So you use a pickup truck for a big-screen TV, a dump truck for dirt, or just a scooter for a letter. And they all work together simultaneously. (All Wi-Fi 6 hardware support MU-MIMO, by the way.)
- ODFMA is when you cut a load of any type or size into small standard pieces that can fit perfectly in any vehicle.
Note that none of these techniques increase the bandwidth of a Wi-Fi band. They only help it work more efficiently in a mixed environment, where devices of multiple Wi-Fi standards and speed grades are present.
Thanks to more advanced quadrature amplitude modulation (QAM) — the way radio frequencies are manipulated — Wi-Fi 6 has much higher ceiling speeds than Wi-Fi 5.
So, ultimately, Wi-Fi 6 beats Wi-Fi 5 in speed.
Target Wake Time: Better battery life
Battery life applies mainly to the client's side. And yes, Wi-Fi 6 clients will generally get better battery life. That's partly thanks to the higher speed — a client will take much less time than older Wi-Fi standards to deliver the same amount of data, hence using less energy.
However, what significantly helps reduce energy use is Wi-Fi 6's new feature called target wake time (TWT). TWT automatically puts the Wi-Fi adapter into sleep mode when idle, no matter how brief, and wakes it back up when necessary.
This method is similar to making a car automatically shut down its engine at a traffic stop and instantly start up when you hit the gas (which is somewhat annoying at first, but you'll get used to it.)
Does Wi-Fi 6 have a better range?
However, if you get a Wi-Fi 6 mesh system, it's a different story. Thanks to faster speeds, you can place the hardware units significantly farther away from one another (than those of Wi-Fi 5) and still get the final Wi-Fi speed fast enough for almost any application at hand. (It's a matter of degrees here.)
In other words, Wi-Fi 6's fast ceiling speed compensates for the signal loss and overheads in the wireless connection between hardware units. As a result, you'll still get a fast connection speed at the far end.
So yes, Wi-Fi 6 works well for wireless mesh Wi-Fi systems, much more so than Wi-Fi 5.
Do existing Wi-Fi clients work with Wi-Fi 6?
The short answer is yes, Wi-Fi 6 is backward compatible and will, in theory, support all existing Wi-Fi clients. In reality, it's a bit more complicated.
Due to other requirements, such as security, efficiency settings, channel width, and so on, many existing clients will need new software drivers to work (well) with Wi-Fi 6 routers.
And for those that are too old, such as 802.11g, 802.11a, or even some 802.11n (Wi-Fi 4) clients, chances are there won't be new drivers for them.
Also, Wi-Fi 6E will only work with Wi-Fi 6E-capable clients. It will not work with legacy clients (Wi-Fi 5 and older). But all Wi-Fi 6 routers will include a 2.4 GHz band that works with all existing clients on the market.
For the most part, you can set your Wi-Fi 6 router to work in a compatible mode. However, it won't deliver fast speeds to Wi-Fi 6 clients in this case. It's a bit of a dilemma.
In my testing, legacy devices proved to work better (had faster Wi-Fi speeds) when working with legacy routers than with Wi-Fi 6 routers, especially on the 2.4GHz frequency band, of which Wi-Fi 6 is indeed slower than Wi-Fi 4 stream by stream.
Should I buy a Wi-Fi 6 router?
Yes, and eventually, you don't have a choice — with the availability of Wi-Fi 6, networking vendors will slowly phase out Wi-Fi 5 hardware.
Wi-Fi 6 is excellent if you have many of the latest Wi-Fi 5 and new Wi-Fi 6 clients. You can upgrade many existing computers to Wi-Fi 6, by the way.
Wi-Fi 6 routers have more than just Wi-Fi speed. These routers tend to be beefy devices with more valuable features.
But, still, for at least the next few years, Wi-Fi 6, especially the Wi-Fi 6E, is not a must-have. A good Wi-Fi 5 router will work just fine for most of us. This post on Wi-Fi 5 gives you more reasons to keep using the old standard.
So, if you need a new router, well, chances are it's sensible to start with a Wi-Fi 6 one. But a Wi-Fi 5 will do, too. It'll work with your Wi-Fi 6 devices anyway.
Wi-Fi 6 is indeed significant in terms of efficiency and speed. But it also pushes the envelope hard on the 5GHz frequency band. And then Wi-Fi 6E requires new hardware, which is far from ideal in terms of adaptation.
I guess it will take Wi-Fi 6 clients a few more years to become as popular as their Wi-Fi 5 counterparts. And then it'll require even more years for us to have real needs or the full experience of Wi-Fi 6.
The move to Wi-Fi 6 is inevitable, but it will take a while. It's a gradual process. In the meantime, in most cases, there's no need to ditch your Wi-Fi 5 equipment deliberately.