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IP Address Validator

Check format, version, range, CIDR notation, and reachability in one click. Free, no account needed.

Enter an IP address above to start validation

We check format, version, range, CIDR, and reachability

What we check

Format Check

Validating IP address format and structure

Version Detection

Detecting IPv4 or IPv6 version

Range Classification

Classifying IP range (private, loopback, public, etc.)

CIDR Notation

Validating CIDR notation if present

Reachability Check

Checking if the address is publicly routable

Learn More

IP Address Validation: IPv4 & IPv6 Checking Explained

IP address formats differ between IPv4 and IPv6. Learn how to validate both quickly and correctly.

What Is IP Address Validation?

IP address validation confirms that a given string is a correctly formatted IPv4 or IPv6 address. With two distinct formats in active use across the internet, it is important to validate both the structure and the range of any IP address before using it in network code.

5 min readRead full guide