How to use the IPv4 to IPv6 Converter tool
- Enter an IPv4 address such as 192.0.2.33.
- Copy the IPv6 form you need.
- Or paste an IPv6 address to decode it.
There is no single “IPv6 version” of an IPv4 address
IPv4 and IPv6 are separate address systems, and a device does not get its IPv6 address by converting its IPv4 one. There are, however, several standard ways to embed an IPv4 address inside IPv6, each used for a specific transition mechanism:
- IPv4-mapped (::ffff:192.0.2.33): how dual-stack operating systems represent IPv4 connections inside IPv6 sockets. You see it in server logs.
- NAT64 (64:ff9b::c000:221): used with DNS64 so IPv6-only networks, including many mobile networks, can reach IPv4 servers.
- 6to4 (2002:c000:221::/48): an older tunnelling method, now deprecated, that derived a whole IPv6 prefix from a public IPv4 address.
- IPv4-compatible (::c000:221): deprecated since 2006 and shown only for reference.
Reading logs and firewall rules
If your web server logs show addresses like ::ffff:203.0.113.5, those are ordinary IPv4 clients seen through an IPv6 socket. Paste one into the tool to extract the IPv4 address. Remember to write firewall rules for both forms if your software does not normalise them.
Privacy
All calculations run in your browser. Nothing you enter is sent anywhere.
Frequently asked questions
Can I reach an IPv4 website from an IPv6-only network?
Yes, if your network provides NAT64 and DNS64, which translate between the two protocols. Most mobile carriers do.
Is ::ffff:a.b.c.d a real IPv6 address on the internet?
No. IPv4-mapped addresses exist only inside a host to represent IPv4 connections and are never routed.
Should I still use 6to4?
No. 6to4 was deprecated in RFC 7526. Use native IPv6 from your provider or a managed tunnel.
Does this convert my public IP to IPv6?
No. Your IPv6 address is assigned by your network; it cannot be calculated from your IPv4 address.