IPv6 (Internet Protocol version 6) is the modern standard for internet addresses, designed to replace the older IPv4 format that ran out of available addresses in 2011. You can check whether you have an IPv6 address on whatsmy.fyi right now.
Why Does IPv6 Exist?
The original internet address format, IPv4, allows for roughly 4.3 billion unique addresses (232). That sounds like a lot, but the global internet exhausted the available IPv4 pool in February 2011. With billions of smartphones, IoT devices, smart TVs, and connected vehicles all needing internet addresses, IPv4 simply could not scale.
IPv6, defined in RFC 2460 and published in 1998 (with widespread adoption beginning around 2012), uses 128-bit addresses — providing approximately 340 undecillion unique addresses (3.4 × 1038). That is enough to give every atom on the surface of Earth its own IP address, with addresses to spare.
What Does an IPv6 Address Look Like?
An IPv6 address consists of eight groups of four hexadecimal digits, separated by colons:
2001:0db8:85a3:0000:0000:8a2e:0370:7334IPv6 has a shorthand notation that simplifies long addresses:
- Leading zeros within a group can be omitted:
0db8→db8 - One consecutive sequence of all-zero groups can be replaced with
:::2001:db8:85a3:0:0:8a2e:370:7334→2001:db8:85a3::8a2e:370:7334
The loopback address (equivalent to 127.0.0.1 in IPv4) is simply ::1 in IPv6.
IPv4 vs IPv6: Key Differences
| Feature | IPv4 | IPv6 |
|---|---|---|
| Address length | 32 bits | 128 bits |
| Total addresses | ~4.3 billion | ~340 undecillion |
| Example address | 93.184.216.34 | 2606:2800:220:1:248:1893:25c8:1946 |
| NAT required? | Yes (address shortage) | No (abundant addresses) |
| Built-in security | Optional (IPsec) | IPsec originally mandatory |
| Header complexity | Variable length | Fixed length (simpler routing) |
Do You Have an IPv6 Address?
Not everyone has an IPv6 address yet. IPv6 adoption has been gradual and varies by country and ISP. As of 2025, roughly 45–50% of global internet traffic uses IPv6. In some countries (India, Germany, the United States) adoption exceeds 60%. In others, it remains below 10%.
If your ISP supports IPv6 and your router is configured correctly, your device will have both an IPv4 and an IPv6 address simultaneously — this is called a dual-stack configuration. Check whatsmy.fyi to see if you have an active IPv6 address.
Does IPv6 Improve Your Privacy?
In some ways, IPv6 can reduce privacy. IPv4 networks often use NAT (Network Address Translation), which hides many devices behind a single public IP, making it harder to track individual devices. With IPv6, each device can have a globally unique address — in theory making tracking easier.
To address this, IPv6 introduced Privacy Extensions (RFC 4941), which generate temporary, randomized IPv6 addresses for outbound connections. Most modern operating systems (Windows, macOS, iOS, Android) use privacy extensions by default.
Frequently Asked Questions
Will IPv4 be turned off?
No official date has been set for IPv4 deprecation. The transition to IPv6 is gradual. IPv4 addresses continue to work alongside IPv6 on the modern internet. Many ISPs support both simultaneously.
Is IPv6 faster than IPv4?
IPv6 itself is not inherently faster, but it can reduce latency in some scenarios because IPv6 connections do not require NAT translation, which adds a small processing overhead. The difference is typically negligible for end users.
What does ::1 mean in IPv6?
::1 is the IPv6 loopback address, equivalent to 127.0.0.1 in IPv4. It refers to your own device — traffic sent to ::1 never leaves your machine. If whatsmy.fyi shows ::1 as your IPv6 address, it means you are accessing it locally (likely in development mode).
How do I enable IPv6?
IPv6 must be supported by your ISP and enabled on your router. Most modern ISPs support IPv6 — check your router's settings for an IPv6 option. If your ISP supports it and your router is enabled, your devices will receive IPv6 addresses automatically via DHCPv6 or SLAAC.
