The internet needs IPv6 and so does your home network

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Have you ever counted up everything in your home that connects to the internet? There's your phone and laptop, but also the TV and game console, plus maybe a video doorbell and many other smart home devices. It's pretty likely that they're all sharing one public internet address, and it's your router's job to figure out which incoming data belongs to which device. This is because IPv4, the internet's original address system, ran out of fresh addresses back in 2011.

It was replaced by IPv6, which has enough addresses for all the devices in the world to have their own (several trillion times over!) According to Google's IPv6 page, roughly half of its users connect via IPv6, and most of the routers you'll come across today support it alongside IPv4 in a setup called dual stack. IPv6 won't make your Wi-Fi faster, though. If your network works fine, there's no compelling reason to start digging through your router's settings to switch it on.

IPv4 was introduced way back in 1981 as the standard which fixed all addresses at 32 bits. While it created around 4.3 billion addresses, those eventually ran out: the Internet Assigned Numbers Authority assigned its last few blocks to the regional registries in February 2011, and North America's allocation ran dry in September 2015. 

Home routers use Network Address Translation (NAT) to cope with this, which works by the home holding one public address while giving each device inside a private one. Most internet providers now do the same on a much larger scale via carrier-grade NAT, which places groups of customers behind shared addresses.

This carrier-level NAT adds a second layer of translation that your router doesn't control, meaning a connection that comes in from the internet might not be able to find its way to the right customer. That's not really a problem when you're just browsing the web, but it can be if you're gaming online, for example. In 2013, the R&D consortium CableLabs, along with several ISPs, tested a bunch of everyday apps behind ISP NAT. It found that tasks like web browsing and Netflix worked just fine, but peer-to-peer Xbox game connections died when both players shared a public address.

IPv6 was first standardized in 1995 with 128-bit addresses — around 340 undecillion (10^36) of them. That's a number so large it's impossible to comprehend. TechTarget offers some perspective: you could give an IPv6 address to every atom on Earth's surface and there would still be enough to do the same for at least 100 planets of the same size. Put another way: every grain of sand on Earth could have billions of IP addresses, or every person could have several octillion.

IPv6 can't talk to IPv4 directly, however, so today's networks run both as we slowly transition. As Network World has explained, NAT took off enough pressure that many ISPs and businesses had little incentive to make the full switch. Google measured IPv6 use at just under 51 percent of its users on October 17, 2026, up from about 33 percent on the same day in 2020. Globally, France leads at 87 percent while the US sits at 55 percent and China at just over six percent.

With IPv6, all the devices on your home network can have their own public address, which each one builds automatically from a prefix your router advertises. Doing this can solve the issues associated with gaming, since consoles can connect to one another without NAT in the middle. 

There have also been temporary workarounds for this. For example, Xbox multiplayer and chat used (and still use in some cases) Teredo, a tunnel that carries IPv6 over IPv4, to get through home NAT. Microsoft has said that carrier-grade NAT was sticking players behind "strict" networks with degraded multiplayer. Thread, the low-power mesh network used by many devices built for the Matter smart home standard, runs on IPv6 too. Microsoft warns that "some Windows components might not function" if you disable IPv6 in Windows.

Your ISP has to support IPv6 if you want to use it. According to APNIC (the Asia-Pacific internet registry), around 85 percent of Comcast and AT&T users have access, while Frontier sits below 25 percent. If yours is on board, the setting usually has its own menu in your router. On TP-Link routers, for example, it's under Advanced > IPv6; on Eero it's at Settings > Advanced networking > IPv6.

It's worth knowing that when you turn on IPv6, your router's firewall takes on the job NAT used to do. While the internet Engineering Task Force recommends that home routers filter unsolicited inbound IPv6 traffic, its guidance also requires an open "transparent mode" and allows manufacturers to make that the default. Thus, you should make sure the IPv6 firewall is on to improve your router's security. Also, VPN apps that only tunnel IPv4 can let IPv6 traffic slip outside the tunnel. 

Devices that only speak IPv4 will carry on using it, and switching IPv6 off on the router pushes everything back to IPv4. So if your network does what you need it to, leave it alone. When it's time to replace your router, make sure IPv6 is switched on and behind the firewall. If you don't, every device you add from then on is one more squeezed behind that single IPv4 address.