IPv6 is the latest version of the Internet Protocol — the addressing system that assigns unique IP addresses to every device on the internet. It was developed to solve the address exhaustion problem: IPv4 (the old system) only supports about 4.3 billion unique addresses, and we ran out. IPv6 supports approximately 340 undecillion addresses — enough for every atom on Earth to have its own IP.
IPv4 vs IPv6: Key Differences
- Address space: IPv4 = ~4.3 billion addresses | IPv6 = 340 trillion trillion trillion
- Format: IPv4 =
192.168.1.1| IPv6 =2001:0db8:85a3::8a2e:0370:7334 - Header complexity: IPv6 has a simpler, more efficient header structure
- NAT: IPv4 requires NAT to stretch addresses; IPv6 doesn’t need it
- Security: IPv6 was designed with IPSec (encryption) in mind
- Auto-configuration: IPv6 devices can configure their own addresses
Should You Enable IPv6?
For most users, yes — if your ISP supports it. Benefits include faster connections to IPv6-native services (many large sites like Google, YouTube, and Facebook are IPv6-native), better future compatibility, and no need for NAT overhead.
Reasons you might disable it:
- Your VPN doesn’t support IPv6 — creating an IPv6 leak that exposes your real IP
- Your ISP’s IPv6 implementation is buggy (rare but happens)
- Troubleshooting a network issue where IPv6 might be the cause
How to Check If You Have IPv6
Visit tools.examineip.com — if your IPv6 address appears, you have IPv6 connectivity. You can also run ipconfig (Windows) or ifconfig (Mac/Linux) and look for an address starting with numbers like 2001:.
IPv6 and VPN Leaks
Many VPNs only tunnel IPv4 traffic. If your device has IPv6 connectivity and your VPN doesn’t handle it, requests can bypass the VPN tunnel entirely — revealing your real IPv6 address. Check for this with our VPN Leak Test. If you have a leak, either choose a VPN that supports IPv6, or disable IPv6 on your device while using the VPN.