The internet is undergoing its biggest infrastructure upgrade since it was created: the transition from IPv4 to IPv6. But what does this mean for you, and how do you know which one you're using? Visit CheckWhatIsMyIP.com — your IP version (IPv4 or IPv6) is displayed right next to your address.
What Is IPv4?
IPv4 (Internet Protocol version 4) has been the backbone of the internet since 1983. It uses 32-bit addresses written as four numbers separated by dots:
192.168.1.1 or 8.8.8.8
IPv4 supports approximately 4.3 billion unique addresses. That sounds like a lot, but with smartphones, IoT devices, and the global expansion of the internet, we've essentially run out.
What Is IPv6?
IPv6 (Internet Protocol version 6) is the replacement. It uses 128-bit addresses written as eight groups of hexadecimal numbers:
2001:0db8:85a3:0000:0000:8a2e:0370:7334
IPv6 supports 340 undecillion addresses (that's 340 followed by 36 zeros) — enough for every grain of sand on Earth to have its own IP address, billions of times over.
Key Differences
- Address space: IPv4 = 4.3 billion addresses; IPv6 = 340 undecillion addresses
- Format: IPv4 = decimal (192.168.1.1); IPv6 = hexadecimal (2001:db8::1)
- Header: IPv6 has a simpler, more efficient header than IPv4
- NAT: IPv4 often requires NAT (multiple devices sharing one public IP); IPv6 gives every device its own public address
- Security: IPv6 was designed with IPSec built in; IPv4 added it as an afterthought
- Auto-configuration: IPv6 devices can automatically configure their own addresses (SLAAC)
Why Is the Upgrade Happening?
IPv4 Address Exhaustion
The global pool of available IPv4 addresses was officially exhausted in 2011. Regional registries have been running out ever since. Today, the only way to get IPv4 addresses is to buy or lease them from organizations that have surplus — and prices have risen to $40-$60 per address.
IoT Explosion
With billions of IoT devices (smart homes, connected cars, industrial sensors) coming online, each needing an IP address, IPv4 simply can't keep up. IPv6 provides enough addresses for every device imaginable.
Performance Benefits
IPv6 can be faster than IPv4 because it eliminates NAT (which adds latency), has more efficient routing, and supports larger packets natively.
Global IPv6 Adoption
As of 2025, global IPv6 adoption is approximately 45%. Leading countries include:
- India: ~70% (driven by Reliance Jio's IPv6-only mobile network)
- France: ~65%
- Germany: ~60%
- United States: ~50%
- China: ~30%
- Japan: ~50%
How to Check Your Connection
- Visit CheckWhatIsMyIP.com
- Look at the badge next to your IP — it shows "IPv4" or "IPv6"
- If your IP contains dots (like 203.0.113.50), you're on IPv4
- If your IP contains colons (like 2001:db8::1), you're on IPv6
Dual-Stack Explained
Most modern networks use dual-stack — running both IPv4 and IPv6 simultaneously. Your device may have both an IPv4 and IPv6 address. Websites that support IPv6 will use it automatically, while older websites fall back to IPv4.
IPv6 and Privacy
IPv6 raises some privacy considerations:
- Unique per device: Unlike IPv4 with NAT (where all devices share one IP), IPv6 gives each device a unique public address — making individual device tracking easier
- Privacy extensions: Modern operating systems use "privacy extensions" that generate temporary, randomized IPv6 addresses to mitigate this
- VPN considerations: Some VPNs don't fully support IPv6, potentially leaking your real IPv6 address. Use our VPN Leak Test to check
Protecting your IPv6 privacy is important. NordVPN handles both IPv4 and IPv6 traffic, preventing leaks that could expose your real address.
Does IPv6 Affect You?
For most users, the transition happens invisibly — your ISP, operating system, and websites handle it automatically. But it's worth knowing which protocol you're on, especially for:
- VPN users: Ensure your VPN handles IPv6 to avoid leaks
- Gamers: IPv6 can reduce latency by eliminating NAT traversal
- Home server operators: IPv6 gives you direct addressability without port forwarding
- Network administrators: Understanding dual-stack is essential for modern network management