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Network Tools

IP Address Lookup

Look up the country, region, city, ISP, organization, ASN and reverse DNS (PTR) for any public IP address.

Query

What is IP Address Lookup?

An IP address lookup resolves any public IPv4 or IPv6 address into human-readable context: which country and city it's registered in, which ISP or hosting provider owns it, its Autonomous System Number (ASN), and its reverse DNS (PTR) record.

This is the same category of data abuse teams, security analysts and sysadmins pull when they see an unfamiliar address in a server log, firewall alert or email header and need to know whether it's a residential user, a cloud server, or something worth blocking.

How to use the IP Address Lookup tool

  1. 1 Enter any public IPv4 address (e.g. 8.8.8.8) or IPv6 address into the input field.
  2. 2 Click lookup — the tool queries geolocation, ISP/ASN and reverse DNS data in one pass.
  3. 3 Check the ASN and organization fields to see who actually operates that address block (ISP, cloud provider, hosting company).
  4. 4 Check the reverse DNS (PTR) result — it often reveals whether an address belongs to a known cloud provider, VPN, or dedicated server.

When you need this tool

  • Tracing the origin of a suspicious login attempt, failed auth, or spam message found in server logs.
  • Checking whether an address hitting your firewall belongs to a legitimate crawler/CDN or an unknown host worth blocking.
  • Verifying a CDN, load balancer or DNS record is actually pointing at the IP range of the provider you expect.
  • Researching the ASN and hosting provider behind a domain before doing business or peering with it.
  • Confirming the geolocation accuracy of an address used for region-based content or fraud checks.

How it works

The tool queries MaxMind's GeoLite2 database for geolocation, ISP and organization data, resolves the address's ASN (the network block it belongs to), and performs a reverse DNS (PTR record) query against public DNS infrastructure. All three results are combined and returned in a single lookup.

Frequently asked questions

What is an ASN and why does it matter?

An Autonomous System Number (ASN) identifies the network operator that owns a block of IP addresses — an ISP, cloud provider, or large organization. Looking up the ASN tells you who actually controls an address, which is often more reliable than geolocation alone for identifying hosting providers, VPNs and cloud instances.

Can IP lookup identify a specific person?

No. IP lookup reveals network-level information — ISP, approximate location, hosting provider — not personal identity. Tying an IP to an individual legally requires the ISP's subscriber records, which are only released through law enforcement or legal process.

Why does reverse DNS sometimes return nothing?

Not every IP address has a PTR record configured — it's optional and set by whoever controls the address block. A missing PTR record is common on residential connections and some cloud instances, and isn't itself a sign of anything suspicious.

How accurate is the geolocation data?

IP geolocation is generally accurate at the country level (99%+) and reasonably accurate at the city/region level, but it is derived from network registration data, not GPS, so it can be off by a city or more, especially for mobile carriers and VPN exit nodes.

Does this work for IPv6 addresses?

Yes — enter a full IPv6 address and the tool returns the same geolocation, ISP, ASN and reverse DNS data as it does for IPv4.