Learn the differences between IPv4 and IPv6 and why both protocols are still used today.
Every device connected to a network needs an Internet Protocol (IP) address. Think of an IP address like a mailing address for a computer—it tells other devices where to send data. Today there are two versions of the Internet Protocol:
IPv4 addresses are written as four decimal numbers separated by periods.
IPv6 addresses use hexadecimal numbers separated by colons and provide an almost limitless number of addresses.
| Feature | IPv4 | IPv6 |
|---|---|---|
| Address Length | 32-bit | 128-bit |
| Address Format | 192.168.1.1 | 2606:4700:4700::1111 |
| Maximum Addresses | 4.3 Billion | 340 Undecillion |
| NAT Required | Usually Yes | Usually No |
| Broadcast | Supported | Not Used |
| Security | Optional IPsec | Designed with IPsec support |
When IPv4 was designed, nobody imagined billions of smartphones, tablets, servers and IoT devices would all need Internet connectivity. As IPv4 addresses became scarce, technologies like Network Address Translation (NAT) helped delay exhaustion, but they were never intended to be a permanent solution. IPv6 solves this problem by dramatically increasing the available address space.
Yes. Most modern networks run in what's known as a dual-stack configuration, meaning devices support both IPv4 and IPv6 simultaneously. This allows organizations to transition gradually without disrupting existing applications.
Want to know whether you're using IPv4, IPv6, or both? Use our free IP lookup tool to instantly view your public IP address.
Looking for networking tools? Visit our Network Toolbox for free DNS lookup, CIDR calculations, SSL certificate checks, WHOIS lookups and more.