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IP & Domain Owner Lookup
Is this address valid — and whose network is it? Asked of the registries themselves.
Why this exists
Before you block, allow-list or report an address, two questions matter: is it even a real public address, and whose network is it? Private and special-use ranges (RFC 1918, loopback, carrier-grade NAT…) are explained right here in the page; public addresses are looked up in RDAP, the internet registries' structured successor to whois — any TLD, via this site's relay.
🌐 This one makes a network request — on click, the address you typed goes to this server's relay, which asks the responsible internet registry and stores nothing
Ownership answers come from RDAP — the registries’ structured successor to whois. Nothing is looked up until you click; on click, the address goes to this site’s relay, which asks the responsible registry and stores nothing.
Learn the theory