MAC Address Vendor Lookup

Identify the manufacturer behind a MAC address and decode what kind of address it is. Paste any format — 00:1B:63:84:45:E6, 00-1B-63-84-45-E6, 001b.6384.45e6 or 001B638445E6.

Look up a MAC address

Bulk lookup — paste an ARP table

Paste the output of arp -a (Windows), arp -n / ip neigh (Linux), or a router's ARP table. Every line containing a MAC is matched to its IP and vendor — interface and header lines are ignored. Up to 4,096 entries.

Reading a MAC address

OUI	First 3 bytes — the IEEE-assigned vendor block
NIC	Last 3 bytes — assigned by the vendor per device
I/G bit	Lowest bit of byte 1: 0 = unicast, 1 = multicast
U/L bit	2nd-lowest bit of byte 1: 0 = global (OUI), 1 = locally administered

A locally administered address has no vendor — it's set by software: randomised phone Wi-Fi, virtual NICs, VRRP/HSRP, bonded links.

Vendor database

Loaded entries: 52,990. Full IEEE registry loaded.