MAC Vendor (OUI)
Paste a MAC address in any format and get the manufacturer registered for its OUI (local IEEE database), plus an analysis of the U/L bit (locally administered or random?) and the I/G bit (unicast vs multicast).
The manufacturer is looked up in a local IEEE OUI database that ships with the page; nothing is sent to any server.
Enter a MAC to identify the manufacturer. How the first octet bits are read
The first octet of the MAC carries two flags in its two least significant bits:
- I/G bit (bit 0, the least significant): if it is
1the frame is multicast; if0it is unicast. - U/L bit (bit 1): if it is
1the address is locally administered (not assigned by the IEEE) — typical of privacy random MACs; if0it is universal (a real vendor OUI).
Quick rule: if the 2nd hex digit of the first octet is
2, 6, A or E, the U/L bit
is set (locally administered / possibly random).
Local IEEE OUI database · everything runs in your browser · no sign-up · nothing leaves your browser.