MAC Address Lookup & Formatter
Identify network card manufacturers (IEEE OUI lookup), convert MAC delimiters (Cisco, Colon, Hyphen), and inspect multicast bits.
MAC Address Architecture, OUI Vendor Identification & Formatter
Inspect Layer-2 Ethernet MAC hardware addresses, IEEE OUI registries, and delimiter styles.
A Media Access Control (MAC) address is a unique 48-bit identifier assigned to network interface controllers (NICs) for communications at the data link layer (Layer 2) of a network segment. Standard MAC addresses are split into two 24-bit segments: the Organizationally Unique Identifier (OUI) assigned by the IEEE, and the Network Interface Controller (NIC) specific identifier.
How It Works & Underlying Architecture
Our tool analyzes the 48-bit binary pattern of any MAC address. It extracts the first 3 octets to query the IEEE OUI vendor database, inspects the U/L bit (Universal vs Locally Administered) and I/G bit (Unicast vs Multicast), and formats addresses across Cisco dot notation, colon separated, and hyphen separated formats.
Technical Specifications & Standards
| Standards | IEEE 802-2014, IEEE EUI-48 |
| Address Length | 48 bits (6 octets) |
| Formats | 00:1A:2B:3C:4D:5E, 00-1A-2B-3C-4D-5E, 001a.2b3c.4d5e |
Real-World Engineering & Creative Use Cases
- Network Security Auditing: Identifying unauthorized devices connected to corporate switches or Wi-Fi APs.
- Cisco Router Administration: Reformatting standard colon MAC addresses into Cisco dot notation for DHCP reservations.
- Wi-Fi Privacy Verification: Detecting whether mobile devices are using randomized private MAC addresses.
Frequently Asked Questions (FAQ)
What is an OUI in a MAC address?
An Organizationally Unique Identifier (OUI) is the first 24 bits (3 bytes) of a MAC address, assigned by the IEEE to hardware manufacturers like Apple, Cisco, or Intel.
How do I tell if a MAC address is randomized?
Look at the second hexadecimal character of the MAC address. If it is 2, 6, A, or E, the Locally Administered bit is set, indicating a randomized private MAC address.