MAC Address Vendor Lookup

What this tool does

Every network interface — Wi-Fi, Ethernet, Bluetooth — has a MAC address, and its first three octets (the OUI, Organizationally Unique Identifier) are assigned to a specific manufacturer by the IEEE. Paste a MAC address (or just its OUI) and this tool tells you which company made the device.

The full IEEE OUI registry is bundled into the page, so the lookup runs entirely in your browser — nothing is sent to a server, it works offline, and there is no sign-up.

Accepted formats

You can paste a MAC address in any of the common forms, in upper or lower case, and either the full address or just the first three octets:

EUI-64 (8-octet) addresses are accepted too — only the first three octets are needed for the vendor.

Batch lookup: paste several addresses, one per line, to resolve them all at once — you'll get one compact MAC — Vendor line per address (great for an ARP table or a device inventory).

What you get back

• MAC — your address normalized to canonical colon-separated uppercase.
• OUI — the 24-bit prefix used for the lookup.
• Vendor — the registered organization name from the IEEE registry, or a note that the OUI is unassigned (common for randomized / locally-administered MACs).
• Type — decoded from the first octet's two special bits:
  • globally unique (IEEE-assigned) vs locally administered (randomized or manually set — these are not in the registry by design);
  • unicast vs multicast / group address.

FAQ