Why this tool is useful
Use this tool to standardize inventory exports and inspect the two IEEE flag bits without performing an OUI vendor lookup or transmitting hardware identifiers.
Developer & Data · runs locally
MAC Address Normalizer and Bit Inspector
Validate 48-bit MAC addresses, render colon, hyphen and Cisco dotted formats, and inspect unicast/multicast plus universal/local flag bits.
Ready. Your working data stays in this browser.
How it works
The browser accepts plain 12-digit hexadecimal, six byte pairs or three Cisco-style groups, normalizes the 48 bits and reads the group and local flags from the first octet.
Practical example
02-00-5E-10-00-00 becomes 02:00:5E:10:00:00 and is reported as a locally administered unicast address.
Validation
The calculation is deterministic and explains validation errors instead of silently changing invalid input.
Privacy boundary
Input and output remain in this tab. Copy and download happen through browser APIs without a server upload.
Result passport
Every run reports its tool mode, timestamp and input/output size so transformed data can be audited.