IPv4 to IPv6 Address Converter

Create or extract IPv4-mapped IPv6, NAT64 /96, and legacy 6to4 address representations locally.

Local browser processing

Addresses and calculation inputs stay in this browser. They are not uploaded, resolved, scanned, or sent to analytics.

Address or network

NAT64 /96 prefix

Result

Enter values and run the tool to see the local result.

What IPv4 to IPv6 conversion means

IPv4 and IPv6 addresses do not have a universal one-to-one conversion. This tool calculates specific representations: IPv4-mapped IPv6 for software, NAT64 addresses for a configured /96 translator, and legacy 6to4 prefixes. It can reverse only those recognized formats.

How to use the address converter

Enter an IPv4 address, or enter a supported IPv6 address that embeds IPv4.
Keep the well-known NAT64 prefix or replace it with the /96 prefix configured on your network.
Copy the mapped, NAT64, 6to4, hexadecimal, binary, or extracted IPv4 value you need.

Conversion does not create connectivity

The output is address representation and arithmetic. It does not configure DNS64, a NAT64 gateway, routing, tunneling, or firewall rules. 6to4 is shown for legacy analysis, not as a deployment recommendation.

Related network tools

IPv6 Subnet Calculator IPv4 Subnet Calculator

IPv4 and IPv6 conversion questions

Can every IPv6 address be converted to IPv4?: No. Only recognized formats that explicitly embed 32 IPv4 bits can be extracted without additional mapping state.
What is an IPv4-mapped IPv6 address?: It is the ::ffff:0:0/96 format used by APIs and dual-stack software to represent an IPv4 endpoint as an IPv6 value.
What is the NAT64 prefix 64:ff9b::/96?: It is the well-known prefix used for algorithmic IPv4 embedding by compatible translators. A real network may use its own configured prefix.
Should I deploy 6to4?: 6to4 is a legacy transition format. The tool displays it for decoding and compatibility work, not as a modern deployment recommendation.

IPv4 and IPv6 conversion questions

Can every IPv6 address be converted to IPv4?

No. Only recognized formats that explicitly embed 32 IPv4 bits can be extracted without additional mapping state.

What is an IPv4-mapped IPv6 address?

It is the ::ffff:0:0/96 format used by APIs and dual-stack software to represent an IPv4 endpoint as an IPv6 value.

What is the NAT64 prefix 64:ff9b::/96?

It is the well-known prefix used for algorithmic IPv4 embedding by compatible translators. A real network may use its own configured prefix.

Should I deploy 6to4?

6to4 is a legacy transition format. The tool displays it for decoding and compatibility work, not as a modern deployment recommendation.