IPv6 Address Checker

Check your IPv6 address and verify IPv6 connectivity — see whether your internet connection supports IPv6, view your full IPv6 address, and understand your dual-stack network status.

Why Check Your IPv6 Address?

Verify IPv6 connectivity: IPv6 adoption varies by ISP and region — checking confirms whether your connection actually uses IPv6 or remains IPv4-only, which affects privacy (IPv6 leaks device-specific address components) and performance.
IPv6 leak detection with VPNs: Some VPNs handle IPv4 traffic through the tunnel but let IPv6 traffic leak directly — if your IPv6 address appears despite VPN connection, it can reveal your real identity even when IPv4 is hidden.
Network administration and troubleshooting: IPv6 addresses are longer and more complex than IPv4 — quickly checking the full address (including interface ID and prefix) helps diagnose routing and firewall issues in dual-stack environments.
Application compatibility testing: Developers building applications that must support both IPv4 and IPv6 need to verify the address their app sees — dual-stack systems may prefer IPv6 in ways that break IPv4-only logic.
Understanding privacy extensions: Modern operating systems generate temporary IPv6 addresses that change periodically (RFC 4941 privacy extensions) — checking your current IPv6 address helps verify whether these privacy features are working.

Check My IP

How to Check Your IPv6 Address

Visit this page: Your IPv6 address (if you have one) is automatically detected from the HTTP request — no additional steps needed.
Read your IPv6 address: A full IPv6 address looks like 2001:db8:85a3::8a2e:370:7334 — if no IPv6 address appears, your connection is IPv4-only.
Understand the address components: The first 48-64 bits are your network prefix (assigned by ISP); the last 64 bits are the interface identifier (often based on your device's MAC address or generated randomly with privacy extensions).
Check dual-stack status: If both IPv4 and IPv6 addresses appear, you have a dual-stack connection — most modern networks prefer IPv6 when both are available.
Verify VPN IPv6 handling: Connect your VPN, then reload this page — if an IPv6 address still appears from your real ISP (not the VPN provider), your VPN is leaking IPv6 traffic.

Real-World Use Case

A privacy-focused user connects to a VPN service and verifies their IPv4 address has changed to the VPN server's IP. However, when they check for IPv6 specifically, their original ISP-assigned IPv6 address still appears — the VPN has no IPv6 support and is leaking all IPv6 traffic directly. This is a significant privacy issue because modern operating systems increasingly prefer IPv6 connections, meaning most traffic to dual-stack websites is going directly (bypassing the VPN) even while IPv4 shows as protected. The user either disables IPv6 entirely (via OS network settings) or switches to a VPN provider that fully supports IPv6 tunneling. The IPv6 checker was the critical diagnostic that revealed the leak the user would otherwise have never noticed.

Best Practices

Check VPN for IPv6 leak protection: Before relying on a VPN for privacy, always verify it handles IPv6 — either by routing IPv6 through the tunnel or by blocking it entirely and falling back to IPv4-only.
Understand the interface identifier portion: Without privacy extensions, the last 64 bits of your IPv6 address are derived from your device's MAC address (EUI-64 format) — this can uniquely identify your device across networks. IPv6 privacy extensions (RFC 4941) generate random interface IDs that change periodically.
Verify IPv6 privacy extensions are enabled: Check whether your temporary address (privacy extension) is being used rather than your stable address — on Windows, run "ipconfig /all" and look for "Temporary IPv6 Address"; on Linux/Mac, check "ip -6 addr show."
Test IPv6 connectivity for hosting purposes: If running a server accessible over IPv6, verify your IPv6 address from the client side to confirm which address remote users will connect to.
Note that IPv6 changes with privacy extensions: Unlike IPv4 (which may stay the same for days or months), temporary IPv6 addresses change every few hours on systems with privacy extensions enabled — check the current address for each session.

Performance & Limits

IPv6 detection: Displays your IPv6 address if your connection supports it — shows "IPv6 not detected" for IPv4-only connections.
Address type identification: Identifies global unicast addresses (internet-routable), link-local addresses (fe80::/10, not internet-routable), and ULA addresses (fc00::/7, private range).
Dual-stack display: Shows both IPv4 and IPv6 simultaneously for dual-stack connections — view both addresses in one page load.
ISP and geolocation: IPv6 address geolocation and ISP lookup is included — same accuracy as IPv4 geolocation (city-level, ~80-90%).
Privacy extension detection: Indicates whether your IPv6 address appears to use a randomized interface identifier (privacy extensions enabled) versus a MAC-based EUI-64 identifier.

Common Mistakes to Avoid

Ignoring IPv6 when checking VPN protection: Many users verify IPv4 VPN protection but forget to check IPv6 — a dual-stack connection with an IPv6-unaware VPN leaks all IPv6 traffic outside the tunnel.
Confusing link-local IPv6 with public IPv6: Link-local addresses (starting with fe80::) are only valid on your local network segment — they're not internet-routable and don't represent your internet-facing IPv6 identity.
Assuming MAC address privacy because IPv6 is dynamic: Simply having a changing IPv6 address doesn't mean it's privacy-preserving — some operating systems use stable but randomized (not MAC-based) interface IDs that still don't change as frequently as privacy-extension addresses.
Not accounting for IPv6 in firewall rules: Setting up UFW, iptables, or cloud security groups for IPv4 only leaves IPv6 ports wide open — always configure firewall rules for both protocol versions separately.

Privacy & Security

Detection is inherent to internet browsing: Your IPv6 address is included in every HTTP request you make — this tool shows you what is already visible to all websites you visit.
No data stored: The IPv6 address detection is performed per-request with no logging or retention beyond the page session.
Privacy extension awareness: Understanding how your IPv6 address is generated (EUI-64 vs privacy extensions) helps you make informed choices about device fingerprinting risk.
No account required: Check your IPv6 address without registration or personal information.

Frequently Asked Questions

What is IPv6 and how is it different from IPv4?

IPv4 (Internet Protocol version 4) uses 32-bit addresses written as four numbers (e.g., 192.168.1.1), providing approximately 4.3 billion unique addresses — a pool that was exhausted globally around 2011-2019 depending on region. IPv6 uses 128-bit addresses written in hexadecimal (e.g., 2001:db8::1), providing 340 undecillion unique addresses (3.4 × 10^38) — effectively unlimited. IPv6 addresses are longer but eliminate the need for NAT (Network Address Translation), allowing every device to have its own globally unique internet-routable address. IPv6 also has built-in support for IPsec encryption, simplified routing, and stateless address auto-configuration (SLAAC). Most modern networks run dual-stack (both IPv4 and IPv6) with IPv6 preferred when available.

Does having an IPv6 address affect my privacy?

IPv6 has privacy implications that IPv4 typically doesn't. Without privacy extensions, IPv6 addresses include an EUI-64 interface identifier derived from your device's MAC address — this means your device has a globally unique, persistent identifier embedded in its IPv6 address, trackable across different networks and ISPs. RFC 4941 privacy extensions (now widely supported on Windows, macOS, iOS, and Android) generate random, frequently-changing interface identifiers to prevent this tracking. The prefix (first 64 bits) still identifies your ISP and location. For maximum privacy: verify privacy extensions are enabled on your OS, use a VPN that routes IPv6 traffic, or disable IPv6 entirely if you don't need it.

How do I check if my VPN leaks my IPv6 address?

Disconnect your VPN and note your public IPv6 address using this tool. Then connect your VPN and reload the page. If the same IPv6 address appears after VPN connection, your VPN is leaking IPv6 — all IPv6 traffic bypasses the VPN tunnel, potentially revealing your identity to dual-stack websites. If no IPv6 address appears after VPN connection (but you had one before), your VPN may be blocking IPv6 — this prevents leaks but means you can't access IPv6-only services through the VPN. Ideal VPN behavior: routes IPv6 through the tunnel and shows the VPN provider's IPv6 address. Many popular VPN services still don't properly handle IPv6 — Mullvad, ProtonVPN, and ExpressVPN are documented as supporting IPv6 in their tunnels.

Why do I have two IPv6 addresses?

Multiple IPv6 addresses on a single connection is normal and by design. You may see: a link-local address (fe80::) for communication within your local subnet; a global unicast address (2001::/16 range) for internet communication; and a temporary address (also global unicast, but randomly generated and changed periodically by RFC 4941 privacy extensions). The temporary address is used for outbound connections to prevent tracking, while the stable global address is used for inbound connections and server hosting. Operating systems (Windows, macOS, Linux) automatically manage multiple IPv6 addresses per interface — you'll typically use the temporary one for browsing and the stable one for hosting. This tool shows the address your connection is using for outbound HTTP requests, which is typically the temporary privacy address.