A MAC address lookup tool identifies the manufacturer of a network device by checking its MAC address against the IEEE OUI database. Whether you’re a network administrator tracking unknown devices, a security analyst auditing your infrastructure, or a home user curious about what’s connected to your Wi-Fi, this tool gives you instant manufacturer identification.

What Is a MAC Address?

A MAC address (Media Access Control address) is a 48-bit hardware identifier assigned to every network interface controller. Defined in RFC 7042, it serves as a unique identifier for devices on a local network segment. Unlike IP addresses, which can change depending on the network, a MAC address is typically burned into the device’s firmware by the manufacturer.

Each MAC address consists of six groups of two hexadecimal digits, totaling 12 characters. The first three octets identify the manufacturer (the OUI), while the last three octets are assigned by the manufacturer to uniquely identify each device.

MAC Address Formats

MAC addresses can be written in several notations, all representing the same value:

Colon notation: 00:1A:2B:3C:4D:5E (most common on Linux and macOS)
Hyphen notation: 00-1A-2B-3C-4D-5E (standard in IEEE documentation and Windows)
Dot notation: 001A.2B3C.4D5E (used by Cisco devices)

This tool accepts all three formats, so you can paste the address exactly as it appears in your system’s output.

What Is an OUI?

The Organizationally Unique Identifier (OUI) is the first 24 bits (three octets) of a MAC address. The IEEE Registration Authority assigns OUIs to hardware manufacturers. For example, Apple owns several OUI prefixes, so any MAC address starting with those prefixes belongs to an Apple device. The IEEE maintains a public database of over 30,000 registered OUI assignments.

How MAC Address Lookup Works

When you enter a MAC address into this tool, it extracts the first three octets and queries the IEEE OUI database to find the registered manufacturer. The process is straightforward: the OUI portion of the address is matched against known assignments, and the corresponding organization name is returned. This lookup is performed entirely against the publicly available IEEE registry data.

MAC Address vs. IP Address

While both are network identifiers, they operate at different layers. A MAC address works at Layer 2 (Data Link) of the OSI model and identifies devices on a local network. An IP address works at Layer 3 (Network) and enables routing across the internet. MAC addresses are generally fixed to hardware, while IP addresses are dynamically assigned. You need both for network communication — the MAC address gets your data to the right device on the local segment, and the IP address gets it to the right network.

Privacy and MAC Randomization

Modern operating systems now randomize MAC addresses to prevent tracking across networks. Apple iOS (since iOS 14), Android (since Android 10), and Windows (since Windows 10) all generate random MAC addresses when scanning for or connecting to Wi-Fi networks. This means the MAC address your device broadcasts may not reflect its true hardware manufacturer. Randomized addresses typically have the locally administered bit set (the second-least-significant bit of the first octet), which this tool can detect.

Common Use Cases

MAC address lookups are valuable in several scenarios:

Identifying unknown devices on your network by determining their manufacturer
Asset inventory management to catalog hardware across an organization
Security auditing to detect unauthorized or unexpected devices
Network troubleshooting to verify device identity when resolving connectivity issues
Forensic analysis to trace network activity back to specific hardware vendors

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MAC Address Lookup