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IPv4 to IPv6

Convert any IPv4 address to IPv6 notation: the standard ::ffff: mapped form, the fully expanded 8-group form, plus the decimal and hex-word values. Useful for dual-stack socket code, logs and firewall rules.

Convert address

Dotted IPv4 in, IPv6 forms out.

Results appear here.

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IPv4-mapped IPv6 addresses

An IPv4-mapped IPv6 address embeds a 32-bit IPv4 address in the last 32 bits of a 128-bit IPv6 address, prefixed with ::ffff:. The full expanded form pads every group to four hex digits, for example 0000:0000:0000:0000:0000:ffff:c000:0201. This tool shows the mapped, expanded, decimal and hex-word forms together.

Why mapped addresses exist

Mapped addresses let dual-stack software handle IPv4 clients through IPv6 sockets: the OS translates ::ffff:192.0.2.1 back to 192.0.2.1 automatically. You will see them in server logs, firewall rules and socket APIs whenever a program listens on an IPv6 socket but accepts IPv4 connections.

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IPv4 to IPv6 FAQs

What is the IPv6 form of an IPv4 address?
::ffff:192.0.2.1 is the standard mapped form. The ::ffff: prefix marks the last 32 bits as an embedded IPv4 address, which dual-stack sockets understand natively.
Does converting give me IPv6 connectivity?
No. Mapping only changes notation. Your network still needs real IPv6 connectivity (a global unicast address and router support) to reach IPv6 hosts.
Mapped vs expanded form, which do I need?
Use the mapped form ::ffff:a.b.c.d in socket code and logs. Use the fully expanded 8-group form when a parser or firewall rule requires all groups written out.
What about 6to4 addresses?
6to4 embeds IPv4 in the 2002::/16 prefix for tunneling, while ::ffff:0:0/96 is for representing IPv4 peers on dual-stack sockets. They solve different problems; this tool produces the mapped form.
Can I convert private addresses like 192.168.1.1?
Yes. Enter any valid dotted address from 0.0.0.0 to 255.255.255.255, including private ranges like 192.168.x.x and 10.x.x.x. Invalid input shows an error instead of a result.
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