MAC Address Lookup
Identify the hardware manufacturer behind any MAC address by matching its OUI prefix against the official IEEE registry, served from a self-hosted copy on our EU infrastructure.
About MAC Address Lookup
A MAC address is the 48-bit hardware identifier assigned to a network interface, usually written as six pairs of hexadecimal digits. Its first three bytes - the first six hex digits - form the Organizationally Unique Identifier (OUI), a prefix the IEEE assigns to the company that manufactured the interface. Looking up that prefix reveals which vendor made the device.
This lookup takes a full MAC address or just its first six hex digits and matches the OUI against the IEEE registry, returning the registered organization name. Separators don't matter: colons, dashes, dots or none at all are all accepted. The registry is stored as a local dataset on our EU servers, so the query runs entirely on our own infrastructure without contacting any external service.
Alongside the vendor, the tool inspects two control bits in the address. The locally-administered bit indicates an address assigned by software rather than burned in by a manufacturer - these will not appear in the IEEE registry and therefore have no vendor. The multicast bit distinguishes addresses meant for a group of receivers from ordinary unicast addresses that identify a single interface. When neither bit is set, the address is flagged as a universal unicast address.
This matters in practice because modern phones and operating systems increasingly randomize their MAC address for privacy, producing locally-administered values with no manufacturer behind them. Recognizing that case - rather than reporting a false or missing vendor - helps you interpret ARP tables, DHCP leases and Wi-Fi scans correctly.
How to use it
- 1Paste a full MAC address such as 00:1A:2B:3C:4D:5E, or just its first six hexadecimal digits.
- 2Run the lookup - the OUI prefix is matched against the IEEE registry stored on our server.
- 3Read the registered vendor name, plus flags indicating whether the address is locally administered or multicast.
Common use cases
- -Identify the maker of an unknown device seen in ARP tables, DHCP leases or Wi-Fi scans.
- -Inventory and label network hardware by manufacturer.
- -Recognize randomized, locally-administered MACs - common on modern phones - that have no vendor.
- -Confirm a device's network-card vendor during troubleshooting or a security investigation.
Frequently asked questions
- What is an OUI in a MAC address?
- The OUI (Organizationally Unique Identifier) is the first three bytes - the first six hexadecimal digits - of a MAC address. The IEEE assigns each OUI to a specific manufacturer, so it identifies the company that made the network interface.
- How is the vendor of a MAC address determined?
- By matching the address's first six hex digits against the IEEE OUI registry, the public database recording which manufacturer holds each prefix. This tool queries a self-hosted copy of that registry on our EU servers.
- Why does my MAC address show no vendor?
- It is most likely a locally administered, randomized address rather than a real hardware address. Modern phones and operating systems randomize the MAC for privacy, and such addresses are not registered to any manufacturer, so no vendor can be found.
- How can I tell a real hardware MAC from a randomized one?
- Check the second hexadecimal digit: if it is 2, 6, A or E, the locally-administered bit is set, meaning the address was assigned by software rather than burned in by a vendor. This tool flags those addresses automatically.
- Do I need the full MAC address to find the vendor?
- No. Only the first six hex digits - the OUI - determine the vendor. You can enter the complete address or just the prefix, with or without colons, dashes or dots.
- Does the lookup send my MAC address to a third party?
- No. The IEEE registry is stored locally on our EU servers, so the lookup runs entirely on our own infrastructure and your MAC address is never sent to an external service.