MAC Address Lookup

What is MAC Address Lookup?

MAC Address Lookup identifies the manufacturer and organization associated with a MAC address by querying the IEEE OUI (Organizationally Unique Identifier) database. It parses MAC addresses in all common formats — colon-separated (00:1A:2B:3C:4D:5E), hyphen-separated, and dot-separated Cisco notation — and resolves the first 24 bits (OUI) to the registered vendor. The tool also validates MAC address format, identifies multicast versus unicast and locally administered versus globally unique addresses by checking the relevant flag bits.

Network administrators identifying devices, security analysts investigating unauthorized network access, and IT teams auditing device inventory. The tool runs entirely in your browser — your data never leaves your device.

How to Use MAC Address Lookup

1. Enter the MAC address in any standard format — colons, hyphens, or Cisco dot notation
2. View the resolved manufacturer name, address, and OUI registration details
3. Check the address type flags — unicast/multicast and global/local administration
4. Search multiple MAC addresses in batch mode for network audit reports

Common Use Cases

• Identifying unknown devices on a network by their NIC manufacturer
• Verifying that network equipment matches procurement records by vendor OUI
• Investigating rogue devices detected by network monitoring tools like Wireshark or Nessus
• Auditing IoT device inventory by correlating MAC prefixes to device manufacturers

Pro Tips

• The OUI only identifies the NIC manufacturer, not the device maker — a Foxconn OUI might be an iPhone, a PlayStation, or a Dell server since Foxconn manufactures NICs for many brands
• Locally administered addresses (second hex digit is 2, 6, A, or E) won't resolve to a vendor because they're assigned by local admins or virtual machines, not by IEEE
• Modern phones use MAC randomization for Wi-Fi scanning — the address you see in probe requests may differ from the one used after association, so always capture the post-association MAC

Why Use This Tool?

• Privacy-first: All processing happens locally in your browser. No data is transmitted to any server.
• No installation required: Works in any modern browser on desktop or mobile.
• Completely free: No account, no credit card, no usage caps.
• Fast and reliable: Powered by modern Web APIs for near-instant results.

Related Concepts

Learn more about related topics: OUI database, IEEE 802, Network forensics, ARP table.

Frequently Asked Questions