MAC Address Lookup

1. Enter a MAC Address: Input the full 48-bit MAC address or just the OUI prefix (first 6 hex characters). Accepts common formats: colon-separated (00:1A:2B:3C:4D:5E), hyphen-separated (00-1A-2B-3C-4D-5E), or continuous (001A2B3C4D5E).
2. Click Lookup: The tool queries the IEEE OUI database to identify the registered vendor for the MAC prefix. Results display the manufacturer name and, when available, device category information.
3. Interpret Results: The OUI (Organizationally Unique Identifier) is the first 24 bits assigned to a manufacturer by IEEE. The remaining 24 bits are device-specific and assigned by the manufacturer internally.
4. Use for Network Diagnostics: Identify unknown devices on your network by looking up their MAC addresses. Useful for security audits, inventory management, and troubleshooting network connectivity issues.

MAC (Media Access Control) addresses are 48-bit hardware identifiers assigned to network interface controllers. The IEEE assigns 24-bit OUI prefixes to manufacturers, who then assign the remaining 24 bits to individual devices. This creates over 16 million unique addresses per vendor allocation.

The format typically displays as six groups of two hexadecimal digits. Bit 0 of the first octet indicates unicast (0) or multicast (1), while bit 1 indicates globally unique (0) or locally administered (1). Virtual machines and some privacy features use locally administered addresses, making vendor lookup impossible. Modern devices increasingly use MAC randomization for Wi-Fi scanning to prevent tracking, generating temporary random addresses that won't match any OUI database entry.

• Looking Up Randomized MACs: iOS, Android, and Windows now randomize MAC addresses for Wi-Fi scanning and some connections. These locally administered addresses (second hex digit is 2, 6, A, or E) won't match any vendor—they're intentionally random for privacy.
• Expecting Device Model Information: OUI lookup only identifies the manufacturer, not the specific product. Apple's OUI tells you it's an Apple device, but not whether it's an iPhone, MacBook, or Apple TV. The device-specific portion isn't in public databases.
• Confusing MAC and IP Addresses: MAC addresses operate at Layer 2 (data link) and are hardware-based. IP addresses operate at Layer 3 (network) and are software-assigned. They serve different purposes—MAC for local network communication, IP for routing across networks.

Need to find the IP address associated with a device? Use our What Is My IP tool for your current connection. For network planning and IP allocation, try the IP Subnet Calculator.