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ASN Lookup: Free IP Address ASN & Network Search Tool

Look up the organization behind an autonomous system number, or find the ASN for an IP address.

Example:

Results will appear here.

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Analyze network infrastructure, routing paths, and IP ownership with our free ip address asn lookup tool. Enter any Autonomous System Number (ASN), domain name, or IP address to retrieve comprehensive network intelligence, BGP route details, and organization ownership data.

What is an IP Address ASN Lookup?

An ip address asn lookup is a network discovery query used to identify which Autonomous System (AS) owns, manages, and routes a specific IP address or network range. By performing an ip asn lookup, network engineers and security professionals can trace an IP address back to its parent network operator, Internet Service Provider (ISP), or cloud hosting provider.

What is an Autonomous System Number (ASN)?

An Autonomous System Number (ASN) is a unique identifier assigned to a collection of IP networks managed by one or more network operators under a single routing policy.

Managed by global internet registries like IANA, RIPE, ARIN, APNIC, LACNIC, and AFRINIC, ASNs enable Border Gateway Protocol (BGP) routing across the internet, allowing data packets to find the shortest and most secure path between different networks.

How to Perform an IP Address ASN Lookup?

Performing an ip asn lookup is quick and straightforward with our tool:

  • Search by IP Address: Enter any valid IPv4 or IPv6 address (e.g., 8.8.8.8) to instantly trace the ASN and network provider hosting that IP.
  • Search by ASN: Enter an Autonomous System Number (e.g., AS15169) to view all assigned IP ranges, organization details, and peering information.

What Data Does Our IP ASN Lookup Tool Provide?

Our whois asn lookup queries global WHOIS databases and BGP routing tables to deliver complete network insights:

  • ASN Ownership Details: Identifies the company, ISP, hosting provider, or organization that owns the network.
  • IP Address Ranges (IPv4 & IPv6): Displays all IP prefixes and subnets announced by the specific ASN.
  • BGP Routing & Peering Data: Shows upstream providers and network interconnection paths.
  • Geographic Location: Identifies the primary country and region where the network operates.
  • Registration Metadata: Includes allocation dates, registry sources (ARIN, RIPE, etc.), and WHOIS contacts.

Why Perform an IP Address ASN Lookup?

1. Cybersecurity & Threat Intelligence

Security analysts and SOC teams perform an ip address asn lookup to investigate malicious IP addresses, track botnets, and block entire compromised network blocks before they affect local infrastructure.

2. Network Administration & BGP Debugging

Network engineers rely on ASN lookup data to verify BGP announcements, troubleshoot routing anomalies, and audit peering arrangements between Internet Service Providers.

3. Competitor & Hosting Infrastructure Analysis

Discover where websites or online services are hosted. A quick lookup asn search reveals whether a site uses infrastructure from AWS, Cloudflare, DigitalOcean, or private data centers.

How to Use the IP Address ASN Lookup?

  1. Enter Input: Type an ASN (e.g., AS13335 or 13335), an IP address (e.g., 1.1.1.1), or a domain name into the search box.
  2. Execute Search: Click the Search button to process the query.
  3. Analyze Results: Review the full breakdown of owner information, announced subnets, and BGP routing data.

Frequently Asked Questions (FAQs)

How do I find the ASN of an IP address?

Simply enter any IPv4 or IPv6 address into our ip address asn lookup tool above and click search. The tool will immediately retrieve the ASN, network owner name, and BGP route details.

What is the difference between a 2-byte and 4-byte ASN?

Originally, ASNs were 16-bit numbers (ranging from 1 to 65535). Due to rapid internet growth, IANA introduced 32-bit (4-byte) ASNs, expanding the pool to over 4 billion unique numbers.

What is the difference between Public and Private ASNs?

Public ASNs (1 to 64511 and 65552 to 419999) are used for internet routing via BGP. Private ASNs (64512 to 65534 and 4200000000 to 4294967294) are reserved for internal enterprise networks and are not routed on the public internet.