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Finding Your Ethernet Hardware Address

Every Ethernet device has a built-in unique identification number supplied by the manufacturer.

An Ethernet Hardware Address (also known as an adapter address, hardware address, EHA, or MAC address) is six bytes long, but it is normally written as 12 characters using hexadecimal notation, where the digits 0-9 are supplemented by the letters A-F. Some utilities present all 12 characters together, while others separate each pair of numbers (representing one of the six bytes) by a colon or dash. The same address might be displayed in any of the following formats:

aa-00-04-00-06-d4
AA:00:04:00:06:D4
AA00040006D4

Please click the link for your operating system below to obtain the proper instructions.

• MacOS X (pre-10.3)
• MacOS 10.3
• MacOS 10.4
• Windows 98 & Me
• Windows 2000 & XP
• Windows Vista/Windows 7

If you need further assistance, please request help from a Student Tech.