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    ASN Lookup

    Look up Autonomous System Number (ASN) information including network prefixes, peering details, and organization data.

    ASN Information Lookup
    Enter an ASN number (e.g., AS15169 or 15169) or IP address to get detailed information
    ASN Information
    Basic autonomous system details

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    Analyze DMARC policies
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    About Our Tools

    Professional-grade email and DNS diagnostic tools trusted by IT professionals worldwide.

    Free to UseNo RegistrationReal-time Results
    EmailToolBox LogoEmailToolBox

    Professional email testing platform for developers, administrators, and marketers.

    Tools

    • MX Lookup
    • SPF Checker
    • DKIM Checker
    • DMARC Analyzer

    Resources

    • Email Guides
    • API Documentation
    • Blog
    • FAQ

    Support

    • Contact Us
    • Help Center
    • Privacy Policy
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    © 2026 EmailToolBox. All rights reserved.

    EmailToolBox LogoEmailToolBox
    Home
    SuperTool

    All-in-one DNS and email testing tool

    MX Lookup

    Check mail exchange records

    Blacklists

    Monitor IP reputation

    DMARC

    Analyze DMARC policies

    Diagnostics

    Email delivery diagnostics

    Email Health

    Comprehensive email domain health

    DNS Lookup

    DNS record lookup tools

    Header Analyzer

    Email header analyzer

    All Tools

    Browse all available tools

    Super ToolsBlacklistsEmail HealthGuides
    All Tools

    ASN Lookup

    Look up Autonomous System Number (ASN) information including network prefixes, peering details, and organization data.

    ASN Information Lookup
    Enter an ASN number (e.g., AS15169 or 15169) or IP address to get detailed information

    Understanding ASN Information

    Learn about Autonomous System Numbers, network routing, peering relationships, and how to interpret ASN data effectively.

    What is an ASN?
    Understanding Autonomous System Numbers and their role in internet routing

    Autonomous System Number Purpose

    An Autonomous System Number (ASN) is a unique identifier assigned to a network or group of networks that are under the control of a single organization and have a unified routing policy.

    • • Identifies networks in BGP routing
    • • Enables inter-domain routing decisions
    • • Provides network ownership information
    • • Facilitates peering agreements
    • • Helps with network troubleshooting

    ASN Types and Ranges

    Public ASNs
    • • 16-bit: 1-64511
    • • 32-bit: 131072-4199999999
    • • Used for internet routing
    • • Globally unique
    Private ASNs
    • • 16-bit: 64512-65534
    • • 32-bit: 4200000000-4294967294
    • • Internal use only
    • • Not advertised globally

    Key ASN Information Fields

    Organization Name
    The entity that owns and operates the network
    Network Prefixes
    IP address ranges announced by this ASN
    Peering Information
    Details about network interconnections and policies

    Related Tools

    MX Lookup
    Check mail servers
    Blacklist Checker
    Check IP reputation
    DNS Lookup
    DNS record queries
    SPF Checker
    Validate SPF records
    DMARC Analyzer
    Analyze DMARC policies
    Header Analyzer
    Analyze email headers
    DKIM Checker
    Verify DKIM signatures
    WHOIS Lookup
    Domain registration info
    SMTP Test
    Test SMTP connectivity
    SSL Certificate
    Check SSL certificates
    DNS Propagation
    Check DNS propagation
    Ping Test
    Test network connectivity
    Traceroute
    Trace network path
    Subnet Calculator
    Calculate IP subnets
    What Is My IP
    Check your IP address

    Need Help?

    Our tools are designed to be intuitive, but if you need assistance, we're here to help.

    DocumentationContact Support

    About Our Tools

    Professional-grade email and DNS diagnostic tools trusted by IT professionals worldwide.

    Free to UseNo RegistrationReal-time Results
    EmailToolBox LogoEmailToolBox

    Professional email testing platform for developers, administrators, and marketers.

    Tools

    • MX Lookup
    • SPF Checker
    • DKIM Checker
    • DMARC Analyzer

    Resources

    • Email Guides
    • API Documentation
    • Blog
    • FAQ

    Support

    • Contact Us
    • Help Center
    • Privacy Policy
    • Terms of Service

    © 2026 EmailToolBox. All rights reserved.