Look up the owner, ISP, network range, geolocation, and abuse contact for any IPv4 or IPv6 address, free and instant.
IPv4 (like 8.8.8.8) and IPv6 (like 2001:4860:4860::8888) are both fully supported.
The lookup routes to the Regional Internet Registry responsible for the IP, ARIN, RIPE NCC, APNIC, LACNIC, or AFRINIC, over RDAP.
Organization, ISP, ASN, network range in CIDR notation, country, and the registered abuse contact.
The full machine-readable registry object is one click away for deep investigations.
The company that holds the allocation, and the provider actually operating it, often different for cloud and CDN ranges.
The Autonomous System Number identifies the network that routes this IP, key for identifying hosting providers and cloud platforms.
The full block the IP belongs to. Useful when you need to allowlist, block, or investigate an entire range rather than one address.
The registered email for reporting spam, phishing, or attacks originating from this IP or network.
Trace the network owner behind an unknown IP sending email to your domain, a first step in any abuse investigation.
Verify your sending IPs are registered to the expected organization before receiving servers make the same check.
Identify hosting providers and ASNs favored by attackers, spammers, and malicious campaigns.
Confirm the country and RIR region of an allocation for compliance and access-control decisions.
It retrieves registration and ownership information for an IP address from the internet's Regional Internet Registries. Unlike a domain WHOIS, it focuses on network blocks: who holds them, which autonomous system routes them, and who to contact about abuse.
A domain lookup queries registrar data about a domain name; an IP lookup queries RIR data about a network allocation. They answer different questions, who owns this name vs. who operates this network.
Yes, IPv6 allocations are registered with the same RIRs and are fully supported.
The country comes from the registry allocation record, which reflects where the block is registered, usually accurate to country level, but not street-level geolocation.
Use the abuse contact returned by the lookup, it is the registered address the network operator is obligated to monitor for spam and attack reports.
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