Random MAC Address Generator — Format, Case & OUI Options
Options & Actions
Output
MAC (EUI-48) Basics
A MAC address is 48 bits (6 bytes). The first byte’s lowest two bits carry special meaning:
- I/G (bit 0): 0 = unicast, 1 = multicast/broadcast
- U/L (bit 1): 0 = globally unique (vendor OUI), 1 = locally administered
Use the options above to constrain these bits and optionally seed with a vendor OUI or your own 3-byte prefix.
Formats
AA:BB:CC:DD:EE:FF
(colon, default)AA-BB-CC-DD-EE-FF
(hyphen)AABB.CCDD.EEFF
(Cisco dotted-quartet)AABBCCDDEEFF
(plain hex)
Note: Generated values are random and not guaranteed to be suitable for any specific device or policy.
What Is a MAC Address? (EUI-48 Explained)
A MAC address (often called hardware address or layer-2 address) is a 48-bit identifier assigned to
network interfaces for communications on Ethernet, Wi-Fi, Bluetooth and other IEEE 802 networks. It’s usually shown
as six bytes of hexadecimal: AA:BB:CC:DD:EE:FF
. The first three bytes are a vendor prefix known as an
OUI (Organizationally Unique Identifier); the last three bytes are typically assigned by the vendor
or your operating system when using locally administered addresses.
Two Special Bits in the First Byte
- I/G (bit 0): 0 = unicast (individual), 1 = multicast/group
- U/L (bit 1): 0 = globally unique (vendor-assigned), 1 = locally administered
In practice, “unicast + globally unique” is what you’ll see printed on most devices. “Locally administered” is handy for virtualization, containers, privacy randomization, or lab work where you don’t want to collide with a real vendor OUI.
Common Display Formats
AA:BB:CC:DD:EE:FF
(colon-separated)AA-BB-CC-DD-EE-FF
(hyphen-separated)AABB.CCDD.EEFF
(Cisco dotted)AABBCCDDEEFF
(plain hex)
Examples of Vendor Prefixes (Illustrative)
Below are well-known brands with example OUIs often seen in the field. These are for educational purposes; organizations can hold multiple OUIs and allocations change over time.
- Apple — e.g.,
FC:FB:D2
,28:CF:E9
- Google / Nest — e.g.,
3C:5A:B4
,54:60:09
- Intel — e.g.,
F8:16:54
,3C:97:0E
- Cisco — e.g.,
00:1B:54
,9C:57:AD
- Samsung — e.g.,
AC:1F:6B
,80:EA:96
- Dell — e.g.,
D4:6A:6A
,B8:CA:3A
- HPE / Aruba — e.g.,
B4:99:BA
,18:64:72
- Ubiquiti — e.g.,
80:2A:A8
,24:A4:3C
- TP-Link — e.g.,
50:C7:BF
,F4:F2:6D
- ASUS — e.g.,
90:84:0D
,60:A4:4C
- Realtek — e.g.,
00:E0:4C
,D8:32:14
- Microsoft — e.g.,
28:16:AD
,7C:1C:68
- Lenovo — e.g.,
64:DF:0C
,AC:72:89
- LG — e.g.,
F0:18:98
,14:7D:DA
- Sony — e.g.,
EC:1A:59
,F8:46:1C
Global vs. Local Administration
A globally unique address uses a vendor OUI with U/L=0. That implies the device vendor guarantees uniqueness within its allocation. A locally administered address sets U/L=1 and can be minted by your OS or tools like this generator. Many platforms (Windows, macOS, Linux, iOS/Android for Wi-Fi privacy) support random, locally administered MACs to reduce tracking.
Good Practices & Safety
- Use unicast for normal device identities (I/G=0). Avoid multicast unless you know you need it.
- Avoid all-zeros and all-FF values; they’re special and can break tooling.
- In shared networks, confirm your policy before changing MACs—some environments use MAC filtering or security bindings.
- If you need vendor-like addresses for testing, seed with an example OUI and set U/L=1 to avoid clashing with real hardware.