IP Lookup

Geolocation, ISP, ASN, and reverse DNS for any IP address or domain. IPv4 and IPv6 supported, no signup, instant results.

What it checks

A full network profile for any address.

One query, six signals - location, ownership, routing, and reputation.

IPv4 and IPv6 resolution

Accepts a raw IP or a domain name and resolves it to both IPv4 (A) and IPv6 (AAAA) addresses, then runs the lookup against whichever the host actually answers on.

Geolocation

Maps the IP to a city, region, country, and approximate coordinates - the same data CDNs and analytics tools use to localize content and detect anomalies.

ASN and ISP

Reports the Autonomous System Number (ASN), the organization that owns the IP block, and the upstream ISP - the bones of how traffic actually routes on the internet.

Reverse DNS (PTR)

Pulls the PTR record so you can see the hostname the IP resolves backwards to - useful for spotting mail servers, residential ISPs, and cloud provider ranges.

Datacenter detection

Flags whether the address belongs to a known hosting provider, cloud region, or VPN exit - vs a residential or mobile ISP.

What is my IP?

One click reveals your own public IP and runs the same lookup against it, so you can verify VPN routing, ASN, and apparent location at a glance.

How it works

From address to profile in under a second.

No CLI, no signup - paste an IP or a domain and read the report.

Enter an IP or domain

Paste an IPv4 address (e.g. 1.1.1.1), an IPv6 address, or a domain name. The tool handles all three.

We resolve and enrich

If you gave a domain, we resolve it first. Then we query geolocation, ASN, ISP, and reverse DNS data sources in parallel.

Read the profile

You'll see country and city, the owning organization and ASN, reverse DNS, and a clear hosting-vs-residential signal.

Why IP data matters

An IP is a fingerprint, a postcode, and a routing decision.

Same number, three different jobs - and getting any of them wrong is expensive.

Fraud prevention

Datacenter ASNs, mismatched country signals, and high-risk ranges are the first filter most fraud teams apply. An IP lookup tells you whether a signup, payment, or login is coming from where the user claims to be.

Localization

Country-level geo decides currency, tax, language, and compliance - GDPR, CCPA, age gating, regional content licensing. Getting the IP-to-country mapping right is the difference between a working store and a legal letter.

Network forensics

When something weird shows up in your logs, the IP is where the investigation starts. ASN, reverse DNS, and hosting signals tell you in seconds whether you're looking at a scraper, a bot, a cloud function, or a real user.

Reference

IP, ASN, and reverse DNS - what each one means.

The short version of the network concepts that show up in the report.

IPv4 vs IPv6

IPv4 is the classic dotted-quad format (4.2 billion addresses, mostly exhausted). IPv6 is the longer hex format with eight groups - effectively unlimited and now the default for most modern networks.

ASN

An Autonomous System Number identifies a network on the internet - usually an ISP, hosting provider, or large enterprise. Two IPs sharing an ASN belong to the same network operator.

PTR / Reverse DNS

A reverse DNS record maps an IP back to a hostname. Mail servers rely on it to pass spam checks, and it often reveals which cloud region or pool an IP came from.

Datacenter vs residential

Datacenter IPs belong to AWS, GCP, OVH, Hetzner, and similar - frequently used by bots, scrapers, and VPNs. Residential IPs come from consumer ISPs and look much more like real users.

Geolocation accuracy

Country-level lookups are usually right. City-level is best-effort and degrades fast on mobile carriers, VPN exits, and IPs that recently changed allocation.

FAQ

Frequently asked questions.

Quick answers about IP lookup and how to read the results.

How accurate is IP geolocation?

Country and ASN-level data is reliable. City-level data is best-effort - it's correct most of the time for fixed-line connections and frequently wrong for mobile carriers, VPNs, and CGNAT pools. Treat city as a hint, not ground truth.

Can I look up IPv6 addresses?

Yes - paste the full IPv6 address (with colons) and the tool will run the same geolocation and ASN lookups it does for IPv4.

What does the ASN tell me?

The ASN identifies the network operator that owns the IP block. If you see traffic from AS13335, that's Cloudflare. AS15169 is Google. ASNs are how you tell apart real users, cloud workloads, and VPN exits.

Why does the IP look different from what I expected?

If you queried a domain, you got the IP of whichever edge or load balancer answered the lookup - which may be a CDN, not your origin. For your own connection, a VPN or corporate proxy will route through their IPs, not yours.

Is this tool really free?

Yes - no signup, no email harvesting, no usage gate. We rate-limit per-IP to keep it fair, but the lookup is free and instant. The paid product is continuous monitoring.

Can SiteTrak monitor my IP for changes?

Yes. SiteTrak watches the IPs and ASNs your domain resolves to and alerts when they change - useful for catching DNS hijacks, accidental origin exposure, or unannounced CDN migrations.

Keep going

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