Every device needs an IP address to communicate with others on the internet. There are 4.3 billion possible IP addresses in the IPv4 standard we use today. But with 4.66 billion active users on the internet, does that mean some of us don’t have an IP address?
Don’t worry, we all have an IP address to use. But things have certainly changed since the beginning of the IPv4 era—and we’ve rounded up five key facts to keep you informed.
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1. When talking about IP addresses, we’re referring to IPv4
IP (Internal Protocol) is a set of rules used by computers to communicate. When talking about IP addresses, we are mostly referring to those using the IPv4 standard. IPv4 was created in the 1980s when the internet started booming. It uses 32-bit numbers, usually written in dot-decimal notation (e.g., 172.16.254.1), which means there are 2^32, or about 4.3 billion addresses, available for worldwide use.
IPv4 has been in use for decades, so most of our IP addresses are IPv4, not IPv6, the newer IP standard. If you check your IP address—you’re most likely using an IPv4 address.
Read more: What can someone do with my IP address?
2. We’ve run out of IPv4 addresses, not IPv6
On November 25, 2019, RIPE NCC, the institution overseeing global internet resources, released their last remaining IPv4 addresses. Thankfully, the internet continues to function.
This is largely because of technologies like network address translation (NAT), which maps many private IP addresses onto one public IP. There are also markets that sell and reallocate old IPv4 addresses for reuse. But most importantly, the internet will never truly run out of IP addresses thanks to a newer standard: IPv6.
3. IPv6 allows 340 trillion, trillion, trillion IP addresses
IPv6 was first developed in the mid-1990s and launched in 2012. As the latest internet protocol version, IPv6 uses addresses that are 128 bits long, theoretically allowing a whopping 340 undecillion IP addresses for future use.
That’s enough for many times more devices than there are atoms in all of our current devices combined. Long live the internet!
4. Most of us still haven’t switched to IPv6
Don’t worry if you haven’t made the jump to IPv6. In fact, you don’t really have control over which version of IP address you use since it’s assigned by your internet service provider.
Full IPv6 adoption will require all devices, websites, and networks to be IPv6-compatible. For most businesses, upgrading to IPv6 is high effort but low return. As for many internet service providers—they’re able to grow their networks by circulating unused IPv4 addresses among their customers without changing to IPv6. To many, IPv4 is still the path of least resistance, although that may change as the price of recycled IPv4 addresses goes up.
5. IPv4 and IPv6 will coexist for some time
IPv4 and IPv6 will coexist for at least some years—or even another decade—as it’s hard to know when we will all completely move on to the latter. IPv4 and IPv6 aren’t designed to interoperate directly. An IPv4-only device can’t communicate with an IPv6 device without a network address translator, so there will likely be some growing pains. But that’s a problem for network operators and device manufacturers.
Read more: The difference between static and dynamic IP, and how to keep your IP private with a VPN
FAQ: About running out of IP addresses
How many public IP addresses are left?
None, if we’re talking about IPv4 public addresses. In 2019, RIPE NCC (the institution overseeing global internet resources) released their last remaining IPv4 addresses; there are no more new ones to assign. But if we are talking about IPv6 addresses—there are a total of 340 trillion trillion trillion of them. It’s not clear how many of these IPv6 addresses are used or left, but it shouldn’t matter, as it’s unlikely they will run out like IPv4 addresses did.
What happens when we run out of IP?
There’ll simply be more IP addresses created, most likely before the existing ones run out. Let’s take IPv4 addresses as an example. People had already anticipated they would run out one day—which they did in 2019—prompting the creation of more IP addresses (IPv6 addresses) to tackle this issue back in 1998.
Will IPv6 ever run out?
No, they are unlikely to run out. There are 340 trillion trillion trillion IPv6 addresses available, which is sufficient to cover more than the trillion internet devices on earth.
Why is IPv6 not popular?
There’s a lot of cost involved in switching over to IPv6, as many of the existing networking devices and equipment are designed for IPv4. But that’s a problem for network operators and device manufacturers. And since IPv4 is still working fine for now, not many of them have made the move.
FAQs
As the latest internet protocol version, IPv6 uses addresses that are 128 bits long, theoretically allowing a whopping 340 undecillion IP addresses for future use. That's enough for many times more devices than there are atoms in all of our current devices combined. Long live the internet!
Is it possible to run out of IP addresses? ›
There are around 4.3 billion unique IP addresses possible. Now, with an ever-increasing global population crossing the 8-billion mark, and nearly universal access to technology, there are many devices connected to the internet, and it is impossible to assign unique addresses for all of them.
Has the world run out of IPv4 addresses? ›
In November 2019, we exhausted our remaining IPv4 pool. This means that networks in Europe, the Middle East and parts of Central Asia are no longer able to receive “new” IPv4 addresses from us that haven't previously been used by another network.
Is there a finite amount of IP addresses? ›
Both IPv4 and IPv6 addresses come from finite pools of numbers. For IPv4, this pool is 32-bits (232) in size and contains 4,294,967,296 IPv4 addresses. The IPv6 address space is 128-bits (2128) in size, containing 340,282,366,920,938,463,463,374,607,431,768,211,456 IPv6 addresses.
Do you think the world will run out of IP addresses with IPv6? ›
Will IPv6 addresses run out eventually? In practical terms, no. There are 2^128 or 340 trillion, trillion, trillion IPv6 addresses, which is more than 100 times the number of atoms on the surface of the Earth. This will be more than sufficient to support trillions of Internet devices for the forseeable future.
How long until we run out of IP addresses? ›
This newer protocol is based on a 128-digit code, as opposed to the 32 digits of IPv4. This gives us more possible combinations, with 340 undecillion different IPv6 addresses available (one undecillion is equal to one trillion, trillion, trillion). It's unlikely to run out anytime soon (if ever, according to analysts).
How have we overcome running out of IP addresses? ›
Long-term solution
Deployment of IPv6 is the standards-based solution to the IPv4 address shortage. IPv6 is endorsed and implemented by all Internet technical standards bodies and network equipment vendors.
Why don't we run out of an IP address? ›
This is largely because of technologies like network address translation (NAT), which maps many private IP addresses onto one public IP. There are also markets that sell and reallocate old IPv4 addresses for reuse.
What would happen if the internet ran out of IP addresses? ›
A: If networks can't get new IP addresses, it will be much harder for them to grow. They have some options, like making more intensive use of the addresses they already have through address sharing (formally, network address translation, or NAT) or perhaps revisiting which addresses truly need IP addresses.
Will IPv4 ever be totally replaced? ›
While the internet will eventually transition to IPv6, IPv4 will likely remain in use for some time. However, it's advisable to embrace IPv6 to ensure continued compatibility and optimal internet experiences. The evolution of internet protocols is a critical aspect of our connected world.
Implementing IPv6
The size of IPv4 address is 32 bits and contains nearly 4.3 billion IP addresses. However, the size of IPv6 address is 128 bits and contains nearly 340 trillion trillion trillion IP addresses. Hence, IPv6 can help to solve the IPv4 exhaustion effectively because it has a large space compared to IPv4.
What is the solution to the IPv4 shortage? ›
The long term solution is to switch to Internet Protocol version 6 (IPv6). IPv6 has trillions of trillions of addresses, enough to give every computer in the world a unique IP address. Unfortunately, IPv6 is mostly incompatible with IPv4, and implementing it often requires replacing equipment such as routers.
Is there a limit to IP addresses? ›
- For IPv4, the maximum number of unique IP addresses is 4,294,967,296 (2^32). - For IPv6, the maximum number of unique IP addresses is 340,282,366,920,938,463,463,374,607,431,768,211,456 (2^128).
Why haven t we fully switched to IPv6? ›
IPv6 was not designed to be IPv4 compatible
A solution to communicate with devices that still run on IPv4 was not provided. This means that each IPv6 address needs an IPv4 address. Having to run both IPv4 and IPv6 addresses means that there are higher maintenance costs, which operators aren't always willing to pay.
Will we ever go to IPv6? ›
Internet experts believe we'll still be running dual IPv4 and IPv6 networks for at least a few more decades. We've found ways to work around the lack of IPv4 addresses, and very few companies or ISPs are seeing any urgency to rush toward a conversion.
Why are we switching from IPv4 to IPv6? ›
Lengthening the IP address from 32 bits to 128 bits, IPv6 alleviates the IPv4 exhaustion crisis for the conceivable future. Other IPv6 enhancements include improvements in efficiency, performance, and security. Since its adoption, IPv6 migration has been widespread but uneven.
How many IP addresses are possible? ›
The IPv4 address space is a 32 bit field. There are 4,294,967,296 unique values, considered in this context as a sequence of 256 "/8s", where each "/8" corresponds to 16,777,216 unique address values.
Did the internet run out of IP addresses? ›
Despite efforts made to conserve IPv4 space, the Internet Assigned Numbers Authority (IANA) announced in 2011 that the world had officially run out of IPv4 addresses.
Do IP addresses expire? ›
IP addresses aren't permanent. Yours won't change often, but sometimes, due to system maintenance, you'll get a short-term DHCP lease. A short-term DHCP lease is a temporary IP address that expires after a set amount of time. A device that's set up correctly will auto renew the DHCP lease.
