Check if your VPN is leaking your IPv6 address. Many VPNs protect IPv4 but leave
IPv6 completely exposed — revealing your real ISP and location to
every website you visit.
IPv6 leak detection
Tests IPv4 and IPv6 simultaneously · 100% client-side · No data stored
Nothing sent to our servers
Your IPv4 address
VPN routing
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Your IPv6 address
Checking…
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Run the test to check for IPv6 leaks
Click the button above to test your IPv4 and IPv6 addresses simultaneously.
Scored using our published, open-source methodology. View methodology
How an IPv6 leak happens
The 3-step leak mechanism — why your VPN can fail on IPv6
You connect your VPN
Your VPN tunnels all IPv4 traffic through its server — your IPv4 address becomes the VPN's IP, exactly as expected.
VPN ignores IPv6
Most VPNs only tunnel IPv4. Your device still has a live IPv6 address assigned by your ISP — and the VPN doesn't touch it at all.
Websites see your real IP
Any site that supports IPv6 receives your real ISP IPv6 address — bypassing the VPN entirely and exposing your real location.
Who is most at risk from IPv6 leaks
Torrent & P2P users
Trackers and peers can see your real IPv6 address even when your VPN's IPv4 tunnel looks completely clean — a common way torrenting deanonymizes an otherwise-protected connection.
Mobile carrier networks
Most mobile carriers assign native IPv6 by default. A VPN app that only tunnels IPv4 leaves phones exposed on exactly the networks where IPv6 is most likely to be active.
Dual-stack home routers
ISPs increasingly ship IPv6 by default alongside IPv4. A device connected to a VPN can still sit behind a router leaking IPv6 traffic the VPN client never sees or tunnels.
Journalists & activists
Anyone relying on a VPN specifically to hide their real location from a website is exposed the moment that site supports IPv6 and the VPN doesn't explicitly block or tunnel it.
Gamers & streamers
Game platforms and streaming services increasingly support IPv6 lookups — a leak can reveal your real region even while your IPv4 traffic routes through a VPN server abroad.
Public Wi-Fi users
Coffee-shop and airport Wi-Fi networks are rolling out IPv6 support just as fast as home ISPs — one more place a leak can happen without any obvious sign in your VPN app.
How to fix an IPv6 leak
1
Choose a VPN with native IPv6 support
Not every VPN tunnels IPv6 traffic at all — look for a provider that explicitly documents full IPv6 support and tunnels it alongside IPv4, rather than just blocking it as a workaround.
Best fix
2
Turn on IPv6 leak protection in your VPN app
Most major VPN apps have a dedicated IPv6 leak protection toggle in settings — enable it explicitly rather than assuming it's on by default.
Recommended
3
Disable IPv6 at the OS or router level
If your VPN doesn't support IPv6 at all, disabling it system-wide (or on your router) closes the gap entirely — you lose IPv6 connectivity, but nothing can leak that doesn't exist.
Technical fallback
4
Run an IPv6 DNS leak test specifically
An IPv6 DNS leak can happen even when general IPv6 traffic looks blocked. After running the test above, cross-check the resolver it reports against known public IPv6 DNS providers like Cloudflare (2606:4700:4700::1111) or Google (2001:4860:4860::8888) to confirm you're not quietly leaking DNS queries over IPv6.
IPv6 DNS check
IPv4 vs IPv6 — key differences relevant to VPN users
IPv4
Virtually every VPN protocol was built around tunneling IPv4 first — support is close to universal across providers.
Easier to fully hide — a VPN that handles IPv6 at all usually tunnels IPv4 completely, with no partial gaps.
IPv4 address space is exhausted — most home connections now sit behind carrier-grade NAT regardless of VPN use.
IPv6
Support varies a lot between VPN providers — some tunnel it fully, some block it outright, some silently ignore it.
A live IPv6 address is usually assigned directly by your ISP and stays active in parallel with any IPv4-only VPN tunnel.
Increasingly required to reach modern IPv6-only services — the fix isn't avoiding IPv6, it's making sure your VPN actually tunnels it.
IPv6 DNS leaks: a separate failure mode worth checking
A clean IPv6 address result above doesn't automatically mean your DNS is safe. It's
possible for general IPv6 traffic to be blocked while DNS queries still resolve over
IPv6 outside your VPN's tunnel — an IPv6 DNS leak that behaves
differently from a standard IPv4 DNS leak and is easy to miss if you only check one.
To confirm which is happening, compare the resolver reported by this test against
known public IPv6 DNS providers — Cloudflare's 2606:4700:4700::1111 or
Google's 2001:4860:4860::8888 are the two most common. Seeing one of
those isn't inherently bad, but if it's being reached directly over your ISP's IPv6
network instead of through your VPN's own DNS, that's the leak. For a dedicated,
IPv4-focused check, run our DNS leak test as well —
the two tools catch different failure modes.
Frequently asked questions
“What is an IPv6 DNS leak test, and is it different from this test?”
This test checks two things at once: whether your device's IPv6 address itself is exposed, and whether DNS queries are resolving over IPv6 outside your VPN tunnel. An IPv6 DNS leak specifically means your browser is still asking an IPv6 DNS resolver to look up hostnames even though your regular traffic seems to be routed correctly — which is why it's worth checking the resolver shown here against a known IPv6 DNS provider rather than assuming "no visible IPv6 address" means "fully protected."
“What does it mean if my IPv6 DNS resolver is Cloudflare or Google?”
Seeing a recognizable public resolver like Cloudflare's 2606:4700:4700::1111 or Google's 2001:4860:4860::8888 isn't automatically bad — plenty of privacy-conscious setups use those resolvers deliberately. What matters is whether that resolution is happening through your VPN's tunnel or leaking directly from your ISP's network outside it. If your VPN provider runs its own DNS and you're instead seeing Cloudflare or Google being queried directly over your normal IPv6 connection, that's the leak.
“Is an IPv6 leak the same as a regular DNS leak?”
No — they're related but distinct failure modes. A DNS leak (over IPv4) happens when your DNS queries bypass the VPN tunnel entirely, regardless of IP version. An IPv6 leak happens when your VPN doesn't tunnel IPv6 traffic at all, exposing a real IPv6 address alongside a protected IPv4 one. It's possible to have one without the other, which is why it's worth running both our DNS leak test and this IPv6-specific test rather than assuming a clean result on one covers the other.
“My VPN says it "blocks" IPv6 — does that mean I'm safe?”
It depends on what "blocks" means in practice. Some VPNs actively disable IPv6 at the network adapter level, which is genuinely safe — there's no IPv6 address to leak. Others simply don't route IPv6 traffic through the tunnel but leave your OS-level IPv6 connectivity untouched, which means it's still active and reachable by any site that supports it — the same gap a kill switch is supposed to close but often doesn't if it was only ever written for IPv4. Running this test tells you which situation you're actually in, rather than trusting the marketing description.
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