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IPv4 to IPv6 Converter

Convert an IPv4 address to its IPv4-mapped IPv6 form.

Quick answer: enter your details below and click Convert — your result appears instantly, right here in your browser. Nothing you enter is uploaded or stored.
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How to use

  1. Enter an IPv4 address in dotted form.
  2. Check that each of the four numbers is between 0 and 255.
  3. Press Convert to see the mapped IPv6 form.

About this tool

IPv6 addresses can carry an old IPv4 address inside them, written as ::ffff: followed by the familiar dotted IPv4 address. This mapped form is used when IPv6 software needs to talk to an IPv4 host. This tool checks that the input is a valid IPv4 address, with four numbers from 0 to 255 separated by dots, and then shows the mapped form. It does not convert an address to a full native IPv6 address, which would need a different mapping.

Frequently asked questions

Is the mapped form a real IPv6 address?

It is a valid IPv6 format, but it represents an IPv4 host rather than a native IPv6 host. Software that understands mapped addresses uses it to bridge the two.

Why is 256 rejected?

Each part of an IPv4 address is a single byte, so it can only hold values from 0 to 255. Anything larger is not a valid IPv4 address.

Related tools

All tools · Read the guide: IPv4 to IPv6 Converter