MAC vendor lookup: which manufacturer owns this address?
Will look up the IEEE-registered vendor for a MAC address's OUI prefix (its first three bytes) and flag locally-administered or randomised addresses. We are holding this page back while we confirm the IEEE OUI dataset's redistribution terms for a commercial product.
The lookup itself is simple; we are holding this page back until IEEE's OUI dataset redistribution terms for a commercial product are confirmed in writing.
- The registered manufacturer for any MAC address’s OUI prefix
- A note when the address is locally administered or randomised, not factory-assigned
- No shortcuts on licensing — see the FAQ below
Next step
Try the subnet calculator or check what your browser reveals.
How it works and limits
Every MAC address’s first three bytes (the OUI, Organizationally Unique Identifier) are assigned by the IEEE Registration Authority to the manufacturer that requested them, so the prefix alone often identifies the maker of a networked device — useful for spotting an unexpected device type on a network, even without a hostname.
What it will check
- The registered manufacturer name for any MAC address’s OUI prefix.
- A note when the address is a locally-administered or randomised MAC (identifiable from the second-least-significant bit of the first byte) rather than a real factory-assigned address.
Why it is not live yet
IEEE publishes the OUI registry as a public CSV, but its usage page does not spell out redistribution terms for bundling that dataset into a commercial product, and querying IEEE live per request is not a realistic architecture for a free tool. Per AdminKit’s own licence policy (no reuse without a clear licence), this page stays “coming soon” until that is confirmed in writing, rather than shipping on an assumption.
Check manually today
Search the first three bytes of the MAC address (e.g. AC:DE:48) in the IEEE’s own public OUI listing, or in any of
the many free OUI lookup tools that already clear this question for their own use. Remember that a locally
administered or randomised address (common on modern phones and laptops) will not match any manufacturer.
Frequently asked questions
Why is this tool not live yet?
The lookup itself (first three bytes of a MAC address, the OUI, mapped to a manufacturer) is simple; the IEEE's public OUI registry page does not clearly state redistribution terms for bundling the dataset into a commercial product. We would rather confirm that in writing with IEEE than ship on an assumption, per AdminKit's own licence policy.
Why doesn't this identify my phone, once it ships?
Android 10+ and recent iOS/desktop OSes randomise the MAC address used per network by default, specifically to prevent this kind of tracking — OUI lookup will work best for fixed infrastructure like routers and IoT devices, not personal phones.