RunTheTests

MAC Vendor (OUI) Lookup

Format any MAC address and read the properties encoded in it.

System verdict

RESULT

00:1A:2B:3C:4D:5E — universally administered unicast

The address is universally administered, so its first three bytes are a real IEEE vendor prefix. Look it up in the vendor tool to name the manufacturer.

Diagnostic telemetry
Colon notation
00:1A:2B:3C:4D:5E
Hyphen notation
00-1A-2B-3C-4D-5E
Cisco notation
001a.2b3c.4d5e
OUI (vendor prefix)The first three bytes, assigned to a manufacturer by the IEEE
00:1A:2B
AdministrationBurned in by the manufacturer
Universally administered
Cast
Unicast

What this cannot tell you

  • Reads the properties encoded in the address itself. It does NOT name the manufacturer — that needs the IEEE vendor database, which the vendor-lookup tool carries separately.
  • A locally-administered address has no real vendor behind it, so its prefix identifies nothing.

How this calculation works

A MAC address is six bytes. The first byte carries two meaningful bits — one says whether the address was assigned by a manufacturer or by software, the other whether it is unicast or multicast — and the first three bytes are the vendor prefix. This tool normalises the notation and reads those properties straight from the bits.

What the results mean

OUI (vendor prefix)
The first three bytes, assigned to a manufacturer by the IEEE. Naming the vendor needs the IEEE database, which this tool does not include.
Locally administered
The address was set by software, not burned into hardware. Normal for virtual machines, containers and phones using randomised Wi-Fi addresses.
Universally administered
A real hardware address with a genuine vendor prefix.
Multicast
Addressed to a group of devices rather than one. A unicast address targets a single device.

Frequently asked questions

Why does my phone show a random MAC?

Modern phones use a different, randomly generated MAC for each Wi-Fi network to stop networks tracking you across locations. These are locally administered, which this tool will show — and their vendor prefix is meaningless by design.

Can you tell me the manufacturer?

Not from this tool. The vendor prefix shown here is real, but turning it into a company name needs the IEEE OUI registry. Use the MAC vendor lookup tool for that.

More in NetMath