MAC Address Generator
Generate random MAC addresses for testing and lab environments.
Generate random MAC addresses in any of the standard formats — colon (aa:bb:cc:dd:ee:ff), hyphen, or dotted (Cisco-style). Useful when you need throwaway addresses for tests without risking collision with real hardware.
Common use cases: seeding device records in a test database, simulating multiple clients on a lab network, generating example addresses for documentation, and creating placeholder MACs for fixtures and mocks.
Generated MAC Addresses
Frequently asked questions
What does a MAC address actually identify?
A specific network interface — typically a single Ethernet or Wi-Fi adapter. A laptop with Wi-Fi, Ethernet and Bluetooth has three different MAC addresses. The address is burned in at manufacturing time, though most operating systems now support MAC randomisation for privacy.
Why are the first six hex digits called the OUI?
The first 24 bits are the Organizationally Unique Identifier — assigned by the IEEE to the manufacturer (Apple, Cisco, Intel, etc). The remaining 24 bits are the device's serial within that vendor's allocation. Vendor lookup from OUI is how network scanners identify what kind of device is on your network.
What's the second-bit "locally administered" flag?
The second-least-significant bit of the first byte indicates whether the MAC is universally administered (assigned by IEEE) or locally administered (chosen by the user/OS). Generated/randomised MACs typically set this bit to avoid colliding with real hardware.
Are these addresses safe to use on a real network?
Generally yes — randomised MACs with the locally-administered bit set are designed for this. But two devices on the same LAN with identical MACs will conflict; if you're generating many for a real environment, ensure they're distinct.