Network Tool
MAC Address Lookup
Identify the hardware vendor from a MAC address or OUI (first 6 hex digits) using the IEEE database.
Enter a MAC address or OUI (first 6 hex digits) to identify the hardware vendor.
This free MAC address lookup identifies the vendor behind any MAC address using the IEEE OUI registry. Enter a MAC address in any common format (colon-separated, hyphen-separated, or dotted) and the tool returns the registered organization, registry type, and address information. The lookup runs against a locally cached copy of the IEEE registry — no packet leaves your browser.
What a MAC address and OUI are
A MAC (Media Access Control) address is a 48-bit link-layer identifier burned into a network interface at manufacture. The first 24 bits (3 octets) form the Organizationally Unique Identifier (OUI), which the IEEE assigns to hardware vendors. The remaining 24 bits are the vendor-assigned device identifier. Because the OUI is globally administered by the IEEE, it uniquely identifies the manufacturer of the interface — allowing you to determine, for example, that a device with MAC prefix 00:50:56 is a VMware virtual machine or that 3C:22:FB belongs to Apple.
IEEE registry types — MA-L, MA-M, and MA-S
The IEEE maintains three OUI registries. MA-L (MAC Address Large) covers the classic /24 OUI block: one vendor prefix, 16 million device addresses. MA-M (Medium) assigns a 28-bit prefix, giving 4,096 addresses per assignment — used by smaller manufacturers. MA-S (Small, formerly IAB) assigns a 36-bit prefix for just 4,096 addresses; it is often used by companies that need a registered OUI for a small product line without committing to a full MA-L assignment. This tool identifies which registry an OUI comes from.
Locally administered and randomized MACs
The second-least-significant bit of the first octet (the L/A bit) indicates whether a MAC is universally administered (IEEE-assigned, L/A = 0) or locally administered (L/A = 1). Locally administered addresses are not registered in the OUI database and will return no vendor match. Modern operating systems — iOS, Android, Windows, macOS, and Linux — use randomized locally administered MACs for Wi-Fi scanning and connections to prevent device tracking across networks. If you see a locally administered address, the OUI lookup will not yield a hardware vendor.
Frequently asked questions
What is an OUI?+
An OUI (Organizationally Unique Identifier) is the first 24 bits of a MAC address, assigned by the IEEE to a hardware manufacturer. It identifies the vendor of the network interface.
Can I find the exact device model from a MAC address?+
No. The OUI identifies the vendor (e.g., Cisco, Intel, Apple), but the remaining 24 bits are assigned arbitrarily by the vendor and are not publicly mapped to specific models. You can narrow it down to a product family only if the vendor publishes their internal allocation scheme, which most do not.
What is a randomized MAC address?+
A randomized MAC is a locally administered address generated by the OS to replace the burned-in hardware MAC during Wi-Fi scanning or when connecting to a network. The L/A bit is set to 1. These addresses change periodically and are not registered with the IEEE, so an OUI lookup returns no vendor.
What formats are accepted?+
Standard colon-separated (AA:BB:CC:DD:EE:FF), hyphen-separated (AA-BB-CC-DD-EE-FF), and Cisco dotted (AABB.CCDD.EEFF) formats are all accepted. The tool normalizes the input before looking up the OUI.