MAC Address API
Validate, reformat and analyse MAC (EUI-48) addresses — entirely locally. The format endpoint accepts a MAC in any common notation — colon (aa:bb:cc:dd:ee:ff), hyphen (aa-bb-…), Cisco dotted (aabb.ccdd.eeff) or bare (aabbccddeeff) — and returns it in the notation you ask for plus all the others, in upper or lower case, normalising messy input into a clean canonical form. The info endpoint analyses an address: it splits the OUI (the manufacturer prefix) from the NIC portion, reports whether the address is unicast or multicast (the I/G bit) and whether it is universally or locally administered (the U/L bit), flags the broadcast address, and derives the Modified EUI-64 interface identifier and the matching IPv6 link-local address (fe80::…) per RFC 4291. Everything is computed locally and deterministically, so it is instant and private — no lookups, no third-party calls. Ideal for network automation and IPAM, switch/router and firewall tooling, device inventory and asset management, DHCP and provisioning, and IPv6 SLAAC work. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This formats and analyses the address; to look up the manufacturer behind a MAC use a MAC-vendor API.
api.oanor.com/macaddr-api