MAC Address Lookup

Analyze MAC addresses to understand their structure and properties. Learn about OUI, unicast/multicast, and locally/universally administered addresses.

Examples:

About MAC Address Structure

A MAC address is 48 bits (6 bytes) long. The first byte contains two important bits: bit 0 (LSB) determines unicast (0) or multicast (1), and bit 1 determines if the address is universally administered (0) by the manufacturer or locally administered (1) by the network admin.

Understanding the Bits:

  • • Bit 0 (LSB of byte 0): Unicast (0) / Multicast (1)
  • • Bit 1 (of byte 0): Universal (0) / Local (1)
  • • Remaining 46 bits: Unique identifier

Common Prefixes:

  • • 01:00:5E - IPv4 Multicast
  • • 33:33 - IPv6 Multicast
  • • FF:FF:FF:FF:FF:FF - Broadcast
  • • 02:xx:xx - Locally Administered

What is MAC Address Lookup?

MAC Address Lookup identifies the manufacturer or vendor of a network device by analyzing its MAC address. The first 24 bits (OUI - Organizationally Unique Identifier) are assigned by IEEE to manufacturers, making it possible to determine which company produced a network interface card or device.

Our tool maintains a comprehensive database of OUI assignments, instantly matching MAC addresses to their registered vendors. It supports all MAC address formats (colon, hyphen, dot-separated) and provides detailed manufacturer information including company name, address, and additional context.

Why Look Up MAC Addresses?

Identifying device manufacturers helps with network troubleshooting, security audits, inventory management, and unknown device identification. When you find an unfamiliar device on your network, MAC lookup reveals the manufacturer, helping determine if it's legitimate or potentially unauthorized.

Perfect for network administrators managing device inventories, security analysts investigating network intrusions, IT professionals troubleshooting connectivity issues, and home users identifying unknown devices connected to their routers.

Common Use Cases

Network Security: Identify unknown devices on your network during security audits, detect rogue access points, and investigate potential unauthorized access attempts.

Troubleshooting: Determine device manufacturers when investigating network issues, compatibility problems, or firmware update requirements for specific hardware.

Inventory Management: Document network infrastructure, maintain accurate asset inventories, and track hardware vendors across large enterprise networks.

How to Use MAC Address Lookup

Enter any MAC address in any format: colon-separated (AA:BB:CC:DD:EE:FF), hyphen-separated (AA-BB-CC-DD-EE-FF), dot-separated (AABB.CCDD.EEFF), or without separators (AABBCCDDEEFF). The tool automatically detects and validates the format.

View instant results showing the manufacturer name, registered company information, and address details. The tool extracts the OUI (first 6 characters) and matches it against the IEEE database to identify the vendor assignment.

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