Converting an Address in Either Direction
Enter one IPv4 or IPv6 address and select Convert IP Address. An IPv4 input produces three labeled IPv6 representations. A supported IPv6 input returns the IPv4 value embedded in it. The tool recognizes the input version, so you do not need to choose a conversion direction.
Enter the address itself without a URL, port, brackets, subnet prefix, or zone identifier. A valid IPv6 address is not automatically convertible to IPv4. The converter checks for supported address structures instead of treating the final digits of every IPv6 address as an IPv4 address.
The Three Results from an IPv4 Input
The results have different purposes. An IPv4-mapped IPv6 address represents an IPv4 value within an IPv6 address structure. The NAT64 result uses the 64:ff9b::/96 prefix. The 6to4 result uses the legacy transition format beginning with 2002.
For the IPv4 input 8.8.8.8, the embedded hexadecimal value is 0808:0808. The output places that value in the position required by each supported format. Those different positions matter: the three results are not interchangeable addresses that can be used in any IPv6 configuration.
Use the label beside each value to keep its purpose clear. A mapped address does not establish translation between networks. A calculated NAT64 address requires a suitable translator, while using a 6to4 address depends on separate network support. The converter does not configure a gateway or tunnel.
When NAT64 Output Can Be Used
The NAT64 result is built with the well-known 64:ff9b::/96 prefix. It can be useful only where the network's NAT64 gateway uses that prefix and can reach the embedded IPv4 destination. If the network uses a different NAT64 prefix, this tool's NAT64 output will not match that network's configuration.
Connections made by domain name may also depend on DNS64, which supplies an IPv6 answer suitable for the translation service. A connection made directly to a calculated IPv6 address does not always require DNS64. Neither case means that an IPv4 website has acquired native IPv6 service.
Read any warning shown with the result. Some IPv4 ranges are not suitable for use with this NAT64 prefix. A calculated address does not make a private destination reachable across the public internet.
Reading 6to4 Results Carefully
6to4 is an older method for carrying IPv6 traffic across IPv4 infrastructure. The converter can create a 6to4 address from an IPv4 value or extract the IPv4 value from an existing 6to4 address. Neither calculation checks whether a working 6to4 service exists on the network.
If the input IPv4 address is unsuitable for public use, the result includes a warning about using the derived 6to4 address for a connection. Do not interpret a displayed address as confirmation that a tunnel is configured or that remote traffic can reach it.
Extracting an Embedded IPv4 Address
Reverse conversion supports IPv4-mapped addresses, NAT64 addresses within 64:ff9b::/96, and 6to4 addresses within 2002::/16. When extraction succeeds, the result identifies the format and displays the recovered IPv4 value. For a NAT64 address containing a private IPv4 value, the result warns that the address cannot be used with this NAT64 prefix.
An ordinary IPv6 address outside those supported structures returns a valid but unsupported message. That is not a format error. It means the converter cannot extract an IPv4 value using one of its supported methods; other IPv6 structures can also carry IPv4 information.
Taking a Result into Another Check
Each IPv6 result can be copied or opened in the compression and expansion tool. That formatting step shows another written form of the same value. It does not change which conversion method produced the address.
A public IPv4 value extracted from a supported address can also be passed to an IP details lookup when the result offers that action. Keep the conversion label and any warning with your notes, because an extracted value alone does not establish ownership, connectivity, or a device's physical location.
