MAC Address Lookup
Identify network device manufacturers by their MAC address in seconds.
Enter MAC Address
How to Find Your MAC Address
Windows:
ipconfig /allLook for "Physical Address" in your network adapter info
Mac/Linux:
ifconfigLook for "HWaddr" or "ether" entries
Network Router:
Check your router's connected devices page (usually 192.168.1.1 or 192.168.0.1)
Understanding MAC Addresses
What is a MAC Address?
MAC stands for Media Access Control. It's a physical address used to identify devices on a local network. Unlike IP addresses (Layer 3), MAC addresses work at Layer 2 (Data Link Layer).
Format: 00:1A:2B:3C:4D:5E (48 bits or 6 octets)
What is OUI?
OUI (Organizationally Unique Identifier) is the first 3 octets (24 bits) of a MAC address. It identifies the manufacturer of the network interface card.
Example: In 00:1A:2B:3C:4D:5E
The OUI is assigned by IEEE, the last 3 octets are unique per manufacturer
MAC Address Structure
First Octet - Special Bits:
- Bit 0: I/G bit (Individual/Group)
- Bit 1: U/L bit (Universal/Local)
- Bits 2-7: OUI identifier
Unicast vs Multicast
Unicast: Least significant bit of first octet is 0. Identifies a single device.
Multicast: LSB of first octet is 1. Sent to multiple devices.
Example: 01:00:5E:xx:xx:xx is used for IPv4 multicast addresses
MAC & ARP Protocol
ARP (Address Resolution Protocol) maps IP addresses to MAC addresses on local networks. Essential for local communication.
- ARP request: "Who has IP X.X.X.X?"
- ARP reply: "I have it, my MAC is..."
- DHCP uses MAC for device identification
MAC & DHCP
When your device gets an IP address (DHCP), the DHCP server uses your MAC address to:
- Identify your unique device
- Assign appropriate IP addresses
- Maintain device-to-IP mappings
- Facilitate static IP assignments
Real-World Applications
Network Administration:
- Device tracking on networks
- MAC filtering for security
- DHCP reservations
- Wake-on-LAN features
Networking Certification:
- Understanding Layer 2 protocols
- ARP (Address Resolution Protocol)
- Switching and VLAN concepts
- MAC address table learning
Example MAC Addresses by Manufacturer
Cisco:
00:0C:85:xx:xx:xxIntel:
00:3E:E1:xx:xx:xxApple:
00:1F:5C:xx:xx:xxMicrosoft:
00:50:F2:xx:xx:xxDell:
00:14:22:xx:xx:xxQEMU (Virtual):
52:54:00:xx:xx:xx* xx:xx:xx represents the device-specific portion (NIC identifier)