# MAC Analyzer

Split a MAC address into its OUI and NIC bytes, and see what the U/L and I/G bits mean. It decodes structure only and does not name the manufacturer.

Every network interface has a 48-bit MAC address, and its structure says a few things before you look up who made the hardware. The first three bytes are the vendor's OUI, and two bits in the first byte say how the address was assigned and who it targets.

## How to read it

Type an address in any common format. The U/L bit says whether it was burned in at the factory or set in software, such as a VM NIC, a VPN adapter, or a phone randomizing its Wi-Fi address. The I/G bit says whether it targets one device or a group.

It does not name the vendor. Look the OUI up in the IEEE registry for that. A locally administered address will not be in the registry at all.

## Related

- [Subnet & VLAN Calculator](https://www.cyberkit.win/tools/cidr-calculator/)
- [OSI & TCP/IP Model](https://www.cyberkit.win/reference/osi-model/)
- [Network Reference Drill](https://www.cyberkit.win/drills/network-ref/)

Canonical: https://www.cyberkit.win/tools/mac-address/

This runs in the browser. Nothing you enter is uploaded.