MAC vendor lookup
Find the manufacturer of a MAC address from the IEEE registry (MA-L, MA-M and MA-S), see whether it is randomised or multicast, and convert it between formats. Paste many at once. Runs in your browser.
What a MAC address tells you
The first half of a MAC address is an Organisationally Unique Identifier (OUI) that the IEEE assigns to a manufacturer, so it identifies who made the network interface. Larger blocks (MA-L) use 24 bits; smaller registrations use 28 (MA-M) or 36 bits (MA-S), and the lookup matches the longest one.
- Locally administered: the second-lowest bit of the first byte is set. Phones and laptops use random addresses like this for privacy on Wi-Fi, and virtual machines and containers often get them too, so there is no vendor to find.
- Multicast: the lowest bit of the first byte is set, so it is a group address, never a single card. Well-known ones such as IPv4 and IPv6 multicast, VRRP and HSRP are named.
- Formats: colon, Windows-style hyphens, Cisco dotted and bare hex, plus the IPv6 link-local address SLAAC would build from it.
The lookup runs in your browser against a copy of the IEEE registry; only the small slice of the registry for the address's first byte is downloaded. Paste up to 200 addresses at once.
Questions
- Why does a MAC address show no vendor?
- Most often it is a randomised, locally administered address, which by design belongs to no manufacturer. Otherwise the block may be registered privately, or assigned after this copy of the registry was taken.
- Can I find a device's location from its MAC address?
- No. A MAC address only identifies the hardware maker, and it never leaves the local network: routers replace it at every hop.