OUI is not device identity
An OUI usually identifies an organization allocation, not a specific model, owner, physical location, or current network.
TechFinity toolkit
MAC / OUI Lookup
Normalize MAC addresses, inspect the OUI and interface bits, identify likely vendors, and learn what the address actually tells you.
Look up an address
Paste any common notation. Separators and letter case are normalized automatically.
Privacy: vendor lookup sends only the public 24-bit OUI. The device-specific lower 24 bits stay on this server.
How to read a MAC
The first 24 bits are commonly the organizational prefix (OUI). The second-least-significant bit of the first octet indicates universal vs. local administration; the least-significant bit indicates individual vs. group addressing.
b7b6b5b4b3b2U/LI/G
U/L = universal/local. I/G = individual/group.
MAC address field guide
Useful context when troubleshooting switching, Wi-Fi, DHCP, ARP, virtualization, and inventory.
Broadcast address
FF:FF:FF:FF:FF:FF is the Ethernet broadcast destination. It is not a vendor-assigned interface address.
Privacy randomization
Phones and laptops frequently use locally administered MACs during Wi-Fi scanning or per-network association.
Switch troubleshooting
Use the normalized address with a switch MAC table, ARP/ND table, DHCP lease table, or wireless-controller client list.
First-octet flags
The I/G bit distinguishes individual from group addressing. The U/L bit distinguishes universal from local administration.
Common formats
AA:BB:CC:DD:EE:FF, AA-BB-CC-DD-EE-FF, and Cisco-style aabb.ccdd.eeff all describe the same 48-bit value.