MAC Address Lookup
Enter a MAC address to find the manufacturer using the IEEE OUI database.
Accepts formats: AA:BB:CC:DD:EE:FF, AA-BB-CC-DD-EE-FF, or AABBCCDDEEFF
What Is a MAC Address?
A MAC (Media Access Control) address is a 48-bit hardware identifier permanently assigned to a network interface card (NIC) during manufacturing. Written as six pairs of hexadecimal digits (AA:BB:CC:DD:EE:FF), it operates at Layer 2 (Data Link) of the OSI model. Unlike IP addresses, MAC addresses are used for local network communication — your router uses ARP (Address Resolution Protocol) to map IP addresses to MAC addresses within your LAN.
The OUI (Organizationally Unique Identifier)
The first three octets (24 bits) of a MAC address form the OUI, assigned by the IEEE to manufacturers. This is why looking up "00:1A:2B" reveals the manufacturer — Apple, Cisco, Intel, etc. The IEEE maintains the public OUI registry. The remaining three octets (NIC-specific portion) are assigned by the manufacturer, making each MAC address globally unique in theory.
MAC vs IP Address
IP addresses are logical, network-assigned identifiers that change as you move between networks. MAC addresses are hardware-assigned identifiers that (by default) remain constant. When you connect to a WiFi network, your device's MAC is visible to the access point but not to the wider internet. Your router substitutes its own MAC when forwarding packets beyond your local network.
MAC Address Spoofing
MAC spoofing is the technique of changing a device's MAC address in software, despite it being "burned in" to hardware. All major operating systems support MAC spoofing. It is used for privacy (modern iOS and Android randomize MAC addresses per WiFi network), bypassing MAC-based access controls, and penetration testing. The locally administered bit (second-least-significant bit of first octet) distinguishes randomly generated MACs from manufacturer-assigned ones.
Network Security Use Cases
Network administrators use MAC addresses for port security (restricting which devices can connect to switch ports), NAC (Network Access Control), and DHCP reservations (always assigning the same IP to a known MAC). However, MAC-based security is weak as a sole control — spoofing is trivial. It works best as one layer in a defense-in-depth strategy alongside 802.1X authentication and network segmentation.
Frequently Asked Questions
Can I find a device's location from its MAC address?
No. MAC addresses are only visible on the local network segment and do not traverse the internet. You can identify the manufacturer, not the device's location.
Why does my phone show a random MAC address?
Modern iOS and Android devices use randomized MAC addresses per network as a privacy feature, preventing tracking across WiFi networks.
Are MAC addresses truly unique?
Theoretically yes, but duplicates exist due to manufacturing errors and deliberate spoofing. Uniqueness is only required within a local network segment.
Can I change my MAC address?
Yes — all major operating systems allow software MAC spoofing. The change is not permanent and resets on reboot by default unless configured otherwise.