IPTools UK

IPv4 / IPv6 Converter

Convert IPv4 addresses between dotted-decimal, integer decimal, hexadecimal and binary — or expand and compress IPv6 addresses.

About this tool

This converter automatically detects what you enter — a dotted IPv4 address, a plain decimal integer, a hexadecimal value, or an IPv6 address in any valid form — and shows every relevant representation. It also serves as a validator: if the input isn't a recognisable address in any supported format, the tool explains why.

How to use this tool

  1. Enter an address or value, e.g. 192.168.1.1, 3232235521, 0xC0A80101, or 2001:db8::1.
  2. Select "Convert". Results update instantly as you type, and the URL updates so you can bookmark the result.

Frequently asked questions

Why would I need the decimal or hexadecimal form of an IPv4 address?
Some systems, log formats, APIs and older networking equipment store or display IPv4 addresses as a single decimal or hexadecimal integer rather than dotted notation. This tool converts between the two freely in both directions.
What is the difference between IPv6 compression and expansion?
IPv6 addresses can be shortened by replacing one run of consecutive zero groups with "::" and removing leading zeros within each group (compression), or written out in full with all eight groups and leading zeros restored (expansion). Both represent exactly the same address.
How do I convert plain digits — is it read as decimal or hex?
A string of plain digits (e.g. 3232235521) is interpreted as a decimal IPv4 integer. To convert a hexadecimal value, prefix it with "0x" (e.g. 0xC0A80101) or include a letter A–F so it is unambiguous.

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