#mac-address

MAC-address (EUI-48) tooling as an API, computed locally and deterministically. The parse endpoint validates a MAC address given in any common notation — colon, hyphen, Cisco dotted or a bare run of 12 hex digits — and returns it in every standard format, split into its OUI (the first three bytes, assigned to a hardware vendor) and its NIC (the last three, device-specific) parts, plus the 48-bit integer value. The analyze endpoint reads the control bits of the first octet: the least-significant bit is the I/G bit that marks a unicast or multicast address, and the next bit is the U/L bit that marks a universally (vendor-assigned) or locally administered address, and it flags the broadcast address ff:ff:ff:ff:ff:ff. The eui64 endpoint derives the modified EUI-64 interface identifier — flipping the U/L bit and inserting FF:FE in the middle — and the resulting IPv6 link-local address (fe80::/64) used by stateless address autoconfiguration. Vendor name lookup needs the IEEE OUI registry and is not included. Everything is computed locally and deterministically, so it is instant and private. Ideal for networking, IoT, device-management, monitoring and security app developers, MAC-normalisation and IPv6 tools, and networking education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is MAC-address tooling; for IPv4 subnetting use a subnet API and for DNS records a DNS API.

api.oanor.com/macaddress-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