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IP Address LookupIP Address Lookup

Enter an IP address you want to get information about.

What is IP Address Lookup?

IP Address Lookup is a free online tool that reports detailed information about an IP address, including reverse DNS hostname, organization details, ASN (autonomous system number), IP whois, geolocation data, and more.

How to use it?

Using our IP Address Lookup is straightforward. Simply enter the IP address or hostname you want to check into the field above, click the "Look up" button, and the tool will initiate a lookup process.

It supports both IPv4 and IPv6 address types. You can enter a hostname as well. In this case, it will perform a DNS lookup to retrieve the associated IP address and proceed with the analysis.

What information can you get from an IP address?

You can get a wealth of data from just one IP address with our tool:

How it is different from others?

Our IP Address Lookup stands out from others due to its extensive dataset, which includes more comprehensive information gathered from multiple sources, providing users with a deeper level of insight.

Read more about the benefits of our tool here: 7 Reasons Why You Should Choose Our IP Address Lookup Tool.

Usage Scenarios

This IP checker can serve a multitude of professional purposes:

Frequently Asked Questions

What is Reverse DNS?

Reverse DNS, or rDNS, is a technique within the Domain Name System (DNS) used to determine the domain name associated with a given IP address. It operates by querying DNS servers for a pointer (PTR) record, providing a way to link IP addresses to their corresponding hostnames.

Reverse DNS is frequently used in anti-spam filters and is essential in network operations, allowing for the identification of the domain associated with an IP address's source.

What is IP Geolocation?

IP-based geolocation (geopositioning, geo-tracking, geolocalization) is the process of identifying the geographical location of an internet-connected device by its IP address. For the better accuracy, we use multiple IP geolocation databases (IP2Location LITE, DB-IP Lite, and MaxMind GeoLite2) and choose the most appropriate result.

What is an IP WHOIS?

WHOIS is both a protocol and a database that allows one to look up "who is" responsible for a domain or IP address. The IP WHOIS contains information about which organization holds which blocks of IP addresses and their details.

What is an Autonomous System (AS)?

An autonomous system (AS) is a fundamental concept in Internet networking, representing a collection of IP networks under the control of a single organization or entity that shares the same routing policy. Basically, it is a collection of IP routing prefixes that allow Internet-connected systems to communicate with each other.

To illustrate the concept of an AS, let's consider some real-world examples:

  • Internet Service Providers (ISPs)
    Large ISPs like AT&T, Comcast, or Verizon operate as autonomous systems. An ISP may have multiple data centers, points of presence (PoPs), and thousands of IP addresses allocated to its AS.
  • Content Delivery Networks (CDNs)
    Companies like Akamai or Cloudflare also operate their own autonomous systems. Typically, CDNs have multiple servers strategically located around the world and manage the routing of traffic to the closest server to increase the speed of content delivery.
  • Large Corporations
    Multinational corporations often have their own ASes, even though they don't provide Internet connectivity to customers and are not considered ISPs. They use them to manage their internal networks, data centers, and cloud resources. Examples are Google, Facebook, and Microsoft.

The number of IP addresses that can belong to an AS varies widely and depends on the size and infrastructure of the organization that operates it. Large ISPs and cloud providers can have thousands or even millions of IP addresses within their ASNs. In contrast, smaller organizations might have just a few hundred or even less.

What is an ASN?

In order for multiple autonomous systems to interact, each needs to have a unique identifier. An autonomous system number (ASN) is such a unique number used to identify a network on the Internet.

AS numbers are assigned in blocks by the Internet Assigned Numbers Authority (IANA). As of December 2020, the number of allocated ASNs exceeded 99,000.

What is a BGP prefix?

A BGP prefix is a network address written in CIDR notation (IP address followed by a slash and the bit-length of the subnet mask, for example,, which is advertised via Border Gateway Protocol (BGP) and is associated with specific BGP attributes including origin, AS-Path, and other information. The primary function of the BGP protocol is to exchange routing and reachability information among autonomous systems on the Internet.

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