MAC Address Lookup FAQ
What is a MAC address lookup tool?
A MAC address lookup tool is a professional online tool that helps users quickly query and verify detailed information about MAC addresses. A MAC address (Media Access Control Address) is a unique identifier for network devices, consisting of 48 bits (6 bytes), typically displayed in hexadecimal format, such as 00:1B:44:11:3A:B7. This tool supports MAC address vendor lookup, OUI lookup, format validation, IPv6 address conversion, and other features, suitable for network management, device identification, troubleshooting, and other scenarios.
Is the MAC address lookup tool free?
Yes, our MAC address lookup tool is a completely free online tool that can be used without registration or download. You can visit our website at any time, enter a MAC address to quickly query vendor information, OUI identification, format validation, IPv6 address conversion, and other features.
What are the MAC address formats?
MAC addresses have several common formats:
1) Colon-separated (AA:BB:CC:DD:EE:FF) - Most common format
2) Hyphen-separated (AA-BB-CC-DD-EE-FF) - Commonly used in Windows systems
3) Dot-separated (AABB.CCDD.EEFF) - Commonly used in Cisco devices
4) No separator (AABBCCDDEEFF) - Compact format
5) Space-separated (AA BB CC DD EE FF) - Used in some systems
This tool supports input in all common formats.
What is OUI (Organizationally Unique Identifier)?
OUI (Organizationally Unique Identifier) is the first 24 bits (first 3 bytes) of a MAC address, assigned by IEEE to device manufacturers. Through OUI, you can identify the device vendor corresponding to a MAC address. For example, 00:03:93 usually represents Apple devices, and 00:00:0C represents Cisco devices. This tool has a built-in OUI database of common vendors, supports generating MAC addresses for specified vendors, and automatically identifies vendor information corresponding to generated MAC addresses.
What is an IPv6 Link-Local address?
IPv6 Link-Local addresses are special addresses used for local link communication in IPv6 networks, within the fe80::/10 range. This tool uses the EUI-64 standard to automatically convert MAC addresses to IPv6 Link-Local addresses. The EUI-64 conversion process includes: inserting FFFE in the middle of the MAC address and flipping the 7th bit (U/L bit) of the first byte. This is very useful for IPv6 network configuration and debugging.
What is the difference between Unicast and Multicast addresses?
Unicast addresses are used for point-to-point communication, where the least significant bit (IG bit) of the first byte of the MAC address is 0. Multicast addresses are used for one-to-many communication, where the IG bit is 1. This tool generates unicast addresses by default, as this is the most common type of device MAC address. You can switch to generating multicast addresses through options.
What is the difference between Locally Administered Address (LAA) and Universally Administered Address (UAA)?
Universally Administered Addresses (UAA) are assigned by IEEE and have global uniqueness, where the second least significant bit (LG bit) of the first byte is 0. Locally Administered Addresses (LAA) are assigned by network administrators, with LG bit set to 1, and do not conflict with globally unique addresses. This tool generates UAA addresses by default, and you can choose to generate LAA addresses for local network testing.
Can generated MAC addresses be used for real devices?
MAC addresses generated by this tool are for testing, development, education, and demonstration purposes only. It is not recommended to use generated MAC addresses for real network devices, as they may conflict with existing device MAC addresses. If you need to configure MAC addresses for real devices, please use the legitimate MAC address ranges provided by device manufacturers, or contact your network administrator to obtain the correct addresses.
