Private vs Public IP Checker

Check whether an IPv4 address is private, public, or part of a common special-use range such as loopback or link-local.

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What this tool does

This tool checks an IPv4 address against common private and special-use ranges. It helps you quickly identify whether an address is RFC1918 private space, public space, loopback, or link-local.

When this tool is useful

Checking whether an address should be routable on the public internet
Validating NAT and firewall assumptions
Explaining internal vs external addressing in documentation
Spotting link-local or loopback addressing mistakes

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