MAC Vendor Lookup

A MAC address is the 48-bit hardware address of a network interface. The first half (three bytes, e.g. 3C:5A:B4) is the OUI — Organizationally Unique Identifier — which the IEEE assigns to a manufacturer. The second half identifies the individual device.

Use it to identify unknown devices in DHCP leases, ARP tables or a switch's MAC address table — is that new device a printer, a phone or an IoT camera? Note the vendor is whoever made the network chip, so you'll often see a chipmaker like Intel, Realtek or Espressif rather than the brand on the box.

No vendor found? Check whether it's locally administered — the second hex digit is 2, 6, A or E. Phones, Windows and macOS randomize their Wi-Fi MAC per network for privacy, so these never have a vendor. If you need a stable MAC for a DHCP reservation or NAC, have the user turn off "private" or "random" hardware address for that network.