Developer API
MAC Address Lookup API: Vendor, OUI & Device Data
A JSON API for MAC address lookup, vendor identification, and OUI/IEEE block data. Look up one address or batch up to 100 at a time, self-host it if lookups can't leave your network.
1,000 free lookups a month, no card required. Sign up for a key or see plans.
One endpoint, three ways to call it
GET /v1/mac/:mac: a single MAC address or OUI lookupPOST /v1/mac/batch: up to 100 addresses in one request, billed per address looked up- The same lookup and vendor directory as MCP tools an AI agent can call directly
What every result includes
- Registered organization, OUI, and full IEEE block (MA-L, MA-M, MA-S, IAB, or CID)
- Registered country and address, when published
- Administration type, transmission type, and IEEE 802c SLAP quadrant
- EUI-64 and IPv6 link-local derivation
- Randomization confidence, explained in plain English
Run it hosted or run it yourself
Two ways to put the API into production
The MAC address database behind this API is live-synced from IEEE, not a stale snapshot, whichever way you run it.
Hosted
api.macadress.com
Sign up, get a key instantly, and start calling the API. Paid tiers buy requests per minute and lookups per month, not extra fields in the response.
See API plans →Self-hosted
A self-hosted MAC lookup API
The same API and sync engine, licensed for your own servers. No lookup leaves your network. Your own infrastructure determines capacity.
Is it worth it? →FAQ
Common questions about the API
Is there a MAC address lookup API?
Yes. GET /v1/mac/:mac returns the registered vendor, OUI, IEEE block, country, and address type for one MAC address as JSON. 1,000 lookups a month are free, no card required; see /pricing for paid tiers and /docs for the full reference.
Does the API support batch MAC address lookups?
Yes. POST /v1/mac/batch accepts up to 100 addresses in one request and returns a result for each, valid or not, billed per address looked up rather than per request.
Is this a MAC vendor API, an OUI lookup API, or both?
Both, from the same endpoint. Every registered result includes both the classic OUI (the first 3 octets) and the full matched IEEE block, since not every assignment is a /24: MA-M and MA-S blocks go down to /28 and /36.
How current is the MAC address database behind the API?
It's synced from IEEE's own registration records on a recurring schedule, not a one-time snapshot. Every response's meta.database_version and the X-Data-Version header report the date of the sync it was served from.
Is there a self-hosted MAC lookup API?
Yes. The same API and its sync engine are available as a self-hosted license for infrastructure where lookups can't leave the network. See /learn/self-hosted-mac-lookup for what that involves and whether it's worth it for your setup.