IP & Network

IP Address Checker

Validate and normalize an IP address locally on this server without contacting the address or performing geolocation.

Validate an IP address

Whitespace is ignored; ports and CIDR prefixes are not accepted.

IPv4, IPv6 and routability

IPv4 uses 32-bit addresses, while IPv6 uses 128 bits and commonly shortens consecutive zero groups with ::. Normalization changes only the written form, not the address.

Public does not simply mean “not private”

Loopback, link-local, multicast, unspecified, documentation and other reserved ranges also should not be treated as ordinary public Internet destinations. The individual classifications above explain why an otherwise valid address may not be globally routable.

IPv4-mapped IPv6

An address beginning with ::ffff: can embed an IPv4 address. The embedded address still matters when deciding whether a target is public.

What this result means

A valid address can still be private, loopback, link-local, multicast or reserved. Globally routable means suitable for public routing, not that the address is reachable or trustworthy.