What Is My IPv6 Address? How Dual-Stack Networking Works
If an IP checker tool has ever shown you two different addresses, one like 203.0.113.45 and another like 2001:0db8:85a3::8a2e:0370:7334, that's not an error. The first is your IPv4 address, the second is your IPv6 address. You can see both of yours right now at iptrackertools.com/what-is-my-ip.
This guide covers what IPv6 actually is, why you probably already have one, and how dual-stack networking lets your device use both formats without you noticing.
What Is an IPv6 Address?
IPv6 stands for Internet Protocol version 6, the newest version of the Internet Protocol, built to eventually replace IPv4. An IPv6 address is a 128-bit number written as eight groups of four hexadecimal digits, separated by colons.
Example: 2001:0db8:85a3:0000:0000:8a2e:0370:7334
This is usually shortened by dropping leading zeros and collapsing consecutive zero groups with :::
Shortened: 2001:db8:85a3::8a2e:370:7334
It looks more complicated than an IPv4 address, but the structure is consistent once you know the pattern.
Why Was IPv6 Created?
IPv4 only supports around 4.3 billion addresses. With billions of phones, laptops, smart devices, and servers all needing a connection, that number ran out.
IPv6 supports 340 undecillion addresses, a number large enough that running out isn't a realistic concern for the foreseeable future. IPv6 was standardized in 1998, but adoption was slow for years. As of 2026, most major ISPs and networks support it, and most modern devices are assigned both an IPv4 and an IPv6 address at once.
Do You Have an IPv6 Address?
Not everyone does. It depends on:
- Whether your ISP supports IPv6 (most major ones now do)
- Whether your router supports IPv6
- Whether your device's network adapter has it enabled To check right now, visit iptrackertools.com/what-is-my-ip. If your network supports IPv6, your address appears immediately alongside your IPv4 address. If it shows as not detected, your connection is currently IPv4-only.
How to Find Your IPv6 Address
The fastest way is a browser tool: see your current IPv4 and IPv6 address here, both shown at once with no settings menu required.
If you'd rather check manually on your own device, Windows, Mac, iPhone, and Android each show it in a slightly different place, in Command Prompt on Windows, Terminal on Mac, and the Wi-Fi network details screen on phones. For the exact steps on each, see the complete device-by-device guide, which walks through all four along with your router.
One thing worth knowing either way: an address starting with fe80: is a link-local address, not your public IPv6, so don't mistake it for the one websites actually see.
What Is Dual-Stack Networking?
Dual-stack means a device holds both an IPv4 and an IPv6 address at the same time. This is the standard setup for most modern devices and networks during the ongoing transition from IPv4 to IPv6.
How it plays out in practice:
- When your device connects to a server that supports IPv6, it uses IPv6 automatically
- When it connects to a server that only supports IPv4, it falls back to IPv4
- This switching happens invisibly in the background, with nothing for you to configure Most major sites, including Google, Facebook, YouTube, and Netflix, support IPv6. Plenty of smaller or older sites still run IPv4 only, which is exactly why dual-stack exists, so your connection works either way.
IPv6 Privacy: Something Worth Knowing
Unlike IPv4 addresses, which are usually shared across many users through NAT, an IPv6 address can be unique to a single device. In theory, that could allow more precise tracking across networks over time.
To address this, most modern operating systems use IPv6 Privacy Extensions, which rotate your IPv6 address periodically so it can't be used for long-term tracking. This is typically on by default on Windows, Mac, iOS, and Android.
Does a VPN Affect Your IPv6?
Yes, and it's worth checking. Some VPNs only route IPv4 traffic through their tunnel, leaving IPv6 traffic exposed outside the encrypted connection. This is called an IPv6 leak, and it means your real IPv6 address can be visible to websites even while your IPv4 address is hidden.
To check for this, use our DNS leak test or WebRTC leak test. A properly configured VPN should mask both your IPv4 and IPv6 addresses, not just one.
IPv4 vs IPv6: Quick Comparison
| Feature | IPv4 | IPv6 |
|---|---|---|
| Address length | 32-bit | 128-bit |
| Example | 203.0.113.45 | 2001:db8::1 |
| Total addresses | ~4.3 billion | 340 undecillion |
| Created | 1981 | 1998 |
| Status | Nearly exhausted | Growing adoption |
| NAT required | Yes | No |
| Security built-in | Optional | Built-in (IPsec) |
For a deeper look at why these two systems exist side by side and which one actually matters for everyday use, see IPv4 vs IPv6: What's the Difference and Which One Am I Using?
The Short Version
IPv6 is the direction internet addressing is heading, and there's a good chance you already have one without realizing it. Dual-stack networking handles both formats for you automatically. Check your IPv6 address here right now, and if you use a VPN, run the leak tests above to confirm it's protecting both your IPv4 and IPv6 traffic.