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Free ASN Lookup Tool

Instantly look up any Autonomous System Number (ASN) by ASN number, IP address, or organisation name. Get real BGP prefix data, peering information, RIR allocation details, and abuse contacts — no simulation, 100% real data.

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100K+
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ASN Lookup — Autonomous System Information

Enter an ASN number (e.g. 15169), IP address (e.g. 8.8.8.8), or organisation name (e.g. Google) to retrieve full ASN details.

Quick Examples
Querying BGP database…
ASN Lookup Results

Advanced ASN Lookup Features

Real data from live BGP routing databases — not simulated, not cached, not mocked.

ASN Number Lookup

Enter any AS number (with or without the AS prefix) to retrieve the organisation name, country, RIR allocation, and full BGP route data.

IP to ASN Mapping

Find the ASN that owns any IPv4 or IPv6 address. Includes PTR record, prefix announcement, RIR allocation, and peering data.

ASN Search by Name

Search by organisation or ISP name to discover all associated ASNs. Useful for auditing network ownership and identifying related autonomous systems.

BGP Prefix Data

View all IPv4 and IPv6 prefix announcements for any ASN. Understand the full IP address space controlled by an autonomous system.

Peering Information

See BGP peering relationships — which other autonomous systems an ASN peers with over IPv4 and IPv6. Essential for network topology analysis.

Export JSON & TXT

Download full ASN lookup results as JSON for developer use or TXT for documentation. Copy to clipboard for quick sharing.

How to Lookup an ASN

Get complete Autonomous System Number information in four simple steps.

1

Choose Lookup Type

Select "ASN / IP / Name" to search by any format, or use the "IP to ASN" tab for dedicated IP address lookup.

2

Enter Your Query

Type an ASN number (15169 or AS15169), an IP address (8.8.8.8), or an organisation name (Google, Cloudflare, Amazon).

3

View Real Results

Instantly see organisation details, country, RIR allocation, all announced IPv4/IPv6 prefixes, and peering relationships.

4

Export Data

Copy results to clipboard or download as JSON or TXT format for use in network documentation, security audits, or reports.

What Is an Autonomous System Number?

An Autonomous System Number (ASN) is a unique numeric identifier assigned by Regional Internet Registries (RIRs) to a collection of IP networks operated by a single organisation with a unified routing policy. ASNs are the backbone of Border Gateway Protocol (BGP) — the routing protocol that enables the global internet to function by exchanging routing information between different networks.

Every major internet company operates one or more ASNs. Google uses AS15169, Cloudflare operates under AS13335, and Amazon Web Services spans multiple ASNs including AS16509. When you visit a website, your internet traffic is routed across multiple autonomous systems, each identified by its unique ASN, before reaching the destination server.

Our free ASN lookup tool queries live BGP databases to provide real, up-to-date information on any ASN. Whether you need to verify IP address ownership, audit your organisation's ASN details, investigate abuse contacts for spam reports, understand BGP prefix announcements, or analyse network peering relationships — this tool delivers genuine data sourced from authoritative BGP routing databases including bgpview.io and RIPE Stat. Unlike tools that return simulated or cached data, every lookup retrieves fresh, accurate information from the source. Export results as JSON for programmatic use or TXT for compliance documentation — all completely free with no registration required.

Frequently Asked Questions

Common questions about ASN lookup, Autonomous System Numbers, and BGP routing.

An Autonomous System Number (ASN) is a unique identifier assigned to a collection of IP networks managed by a single organisation that presents a common routing policy to the internet. ASNs are used in BGP routing to identify autonomous systems. Examples: AS15169 (Google), AS13335 (Cloudflare), AS32934 (Meta/Facebook).
Enter the ASN number (e.g. 15169 or AS15169), an IP address, or an organisation name into our ASN Lookup tool. The tool queries real BGP databases to return the organisation name, country, BGP prefixes, peering data, and RIR allocation details instantly.
An ASN lookup returns the organisation name, country code, description, website, abuse contact emails, RIR allocation details, IPv4 and IPv6 BGP prefix announcements, peering relationships, and traffic estimation data where available from bgpview.io and RIPE Stat databases.
An IP address identifies a specific device on a network, while an ASN identifies the entire autonomous system — the collection of IP networks operated by an organisation. One ASN can encompass thousands or millions of IP addresses across multiple IP prefix ranges announced via BGP.
As of 2025, there are over 100,000 active ASNs globally. ASNs are managed by Regional Internet Registries (RIRs): ARIN (Americas), RIPE NCC (Europe/Middle East), APNIC (Asia-Pacific), LACNIC (Latin America), and AFRINIC (Africa).
Yes, this ASN Lookup tool queries live BGP routing databases — no simulation, no mock data. It uses bgpview.io as the primary source and falls back to RIPE Stat and ip-api.com for comprehensive coverage. Results are real-time and reflect current BGP routing tables.

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