What Is IPv6 and How Does It Compare to IPv4?
IPv6 (Internet Protocol Version 6) is the latest generation of the Internet Protocol, designed to replace IPv4 and expand the number of available IP addresses worldwide.
While IPv4 uses 32-bit addresses and provides around 4.3 billion total addresses, IPv6 uses 128-bit addresses, offering a virtually limitlessness supply of IP addresses for every device connected to the internet.
Why was IPv6 created?
When IPv4 was created in the early 1980s, 4.3 billion addresses seemed more than enough for global networking needs.
However, with the rapid growth of smartphones, IoT devices, cloud services, and connected appliances, available IPv4 addresses quickly became scarce.
Technologies such as NAT and CGNAT extended the life of IPv4 by sharing addresses, but IPv6 was created to solve the underlying shortage permanently.
How do IPv4 and IPv6 addresses look?
An IPv4 address is written in dotted-decimal format using four numbers separated by dots:
An IPv6 address is written in hexadecimal notation using eight groups of four hexadecimal digits separated by colons:
IPv4 vs IPv6 comparison
| Feature | IPv4 | IPv6 |
|---|---|---|
| Address Length | 32 bits | 128 bits |
| Address Format | Dotted decimal (e.g., 192.0.2.1) | Hexadecimal (e.g., 2001:db8::1) |
| Total Address Pool | ~4.3 billion | ~3.4 × 1038 addresses |
| DNS Record Type | A record | AAAA record |
| NAT Requirement | Common (NAT / CGNAT) | Not required (end-to-end addressing) |
Key advantages of IPv6
- End-to-End Connectivity: Every device can have a unique globally routable address, simplifying peer-to-peer applications and server hosting.
- No Need for CGNAT: Port forwarding issues caused by Carrier-Grade NAT disappear with full IPv6 support.
- Simplified Auto-Configuration: IPv6 supports SLAAC (Stateless Address Autoconfiguration), allowing devices to automatically generate their addresses.
- More Efficient Routing: Streamlined packet header processing reduces workload on network routers.
How to check if you have IPv6 support
You can check whether your ISP and network support IPv6 by visiting the IPScope Public IP Lookup. If IPv6 is enabled on your connection, your IPv6 address will be displayed alongside your IPv4 address.
IPv6 is the long-term solution for internet address expansion. While IPv4 remains widely used through NAT technologies, IPv6 provides the address space needed for the modern internet and simplifies direct end-to-end communication.
Related IPScope guides
Compare both addressing systems in detail in IPv4 vs IPv6.
Learn more about how ISPs share IPv4 addresses in What Is CGNAT and How Can You Tell If Your ISP Uses It?.
