MAC address lookup: vendor and IEEE OUI registry

Identify the manufacturer and understand what each part of a MAC address reveals.

Try

MAC address lookup and OUI lookup, explained

A MAC address lookup tells you which manufacturer a network card belongs to. The first half of the address — the OUI (Organizationally Unique Identifier) — is assigned by the IEEE to a single company. MAClens matches it against the official IEEE registries (MA-L, MA-M and MA-S), always using the most specific prefix.

An OUI lookup goes further than the vendor name: MAClens also reads the address bits to tell whether it is unicast or multicast, globally unique or locally administered (often a random address from a phone), and recognises special addresses and virtual machine conventions such as Docker, VMware or Hyper-V.

Frequently asked questions

+How do I look up a MAC address?

Paste the address in the field above, in any format (00:1A:2B:3C:4D:5E, 00-1A-2B-3C-4D-5E or 001A.2B3C.4D5E), then run the analysis. The vendor, prefix and address type appear instantly.

+What is an OUI lookup?

It is a search of the IEEE registry for the 24-bit prefix (or longer, for MA-M and MA-S blocks) at the start of a MAC address, to find the organisation it was assigned to.

+Why is no vendor found for my address?

The address is probably locally administered: phones and computers use random MAC addresses for privacy, and virtual machines often use local ones. These are not listed in the IEEE registry.

+How up to date is the vendor data?

The IEEE MA-L, MA-M and MA-S registries are downloaded again every day.

+Can I run MAC lookups from my own code?

Yes, the MAClens API returns the full analysis as JSON, with 100 free requests per day.