Introducing the IP Address Validator — IPv4 & IPv6

An IP address is just a string until something checks it — and a valid address isn’t automatically a usable one. The new IP Address Validator checks both, instantly.

What it does

• Validates IPv4 and IPv6, including the :: shorthand and embedded IPv4.
• Detects scope — public, private (RFC 1918), loopback, link-local, multicast, and reserved.
• IPv4 breakdown — class (A–E), 32-bit integer, hex, and binary.
• IPv6 forms — compressed canonical and fully expanded eight groups.
• One-click examples so you can explore well-known addresses.

Why it matters

Treating a private or loopback address as if it were a public, routable one is a real source of bugs and security gaps. Seeing an address’s version and range at a glance makes firewall rules, form validation, and connectivity debugging far more reliable. And if you’ve ever tried to validate IPs with one giant regular expression, a quick test in the Regex Tester shows why parsing-and-checking beats a brittle pattern.

Learn more

Our guide to IPv4 vs IPv6 covers address structure, private ranges, and how to validate correctly in your own code. Then check any address in the IP Address Validator — free, instant, and entirely in your browser.