Random MAC Address Generator
Generate a random MAC address for testing, labs and network configuration. Pick the format and case, optionally set the locally administered bit, then copy the result.
How to generate a MAC address
- Choose a format: colon, hyphen or Cisco dot notation.
- Pick uppercase or lowercase hex digits.
- Decide whether to set the locally administered bit.
- Press Generate, then copy the MAC address.
Examples
Colon format, uppercase
colon, uppercase
02:1A:2B:3C:4D:5E
Hyphen format
hyphen, uppercase
02-1A-2B-3C-4D-5E
Cisco dot format, lowercase
dot, lowercase
021a.2b3c.4d5e
Frequently asked questions
What is a MAC address?
A MAC address is a 48-bit hardware identifier for a network interface, written as six hexadecimal bytes such as 02:1A:2B:3C:4D:5E. It identifies a device on a local network segment.
What does locally administered mean?
It sets a flag in the first byte that marks the address as one you assigned yourself rather than one burned in by a manufacturer. Leaving it on is the safe choice for random addresses so they cannot clash with a real vendor's range.
Which formats are supported?
Three common styles: colon separated (AA:BB:CC:DD:EE:FF), hyphen separated (AA-BB-CC-DD-EE-FF) and the Cisco three-group dot notation (aabb.ccdd.eeff). You can also switch between uppercase and lowercase.
Is this address guaranteed to be unique?
No. The bytes are random, so collisions are possible though very unlikely. These addresses are intended for testing, virtual machines and lab setups, not for guaranteeing global uniqueness.
Does anything get sent to a server?
No. Generation happens entirely in your browser, so it is private and works offline.
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