MAC address vendor lookup
Find the hardware manufacturer behind any MAC address, from its OUI.
Only the OUI is sent to the vendor database. Queries are not stored.
How to look up a MAC address
- Enter a MAC address. Paste a MAC address in any format, e.g. 3C:5A:B4:11:22:33.
- Resolve the vendor. We look up the OUI in the public vendor database.
- See the result. View the manufacturer and the address flags.
How a MAC address is built
A MAC address is 48 bits, usually written as six hex pairs. It splits cleanly in half: the first 24 bits are
the OUI (Organisationally Unique Identifier), a block the IEEE sells to a hardware vendor, and
the last 24 bits are assigned by that vendor to individual devices. So the OUI is what a lookup resolves to a
manufacturer name. You'll see the same address written several ways — 00:1A:2B:3C:4D:5E,
00-1A-2B-3C-4D-5E, or the Cisco-style 001A.2B3C.4D5E — they're identical; only the
separators differ, which is why this tool accepts any of them.
Why the vendor is useful to know
Resolving the OUI to a vendor turns an anonymous hex string into something you can act on. On a network audit it lets you tell an "Espressif" board (likely a smart plug or ESP32 gadget) from an "Apple" or "Samsung" device at a glance, spot a manufacturer that shouldn't be on your Wi-Fi, or attribute traffic in a packet capture to a class of hardware. It's the fastest first pass when an unfamiliar device shows up in your router's client list.
The randomisation caveat
Modern phones and laptops increasingly use randomised MAC addresses for privacy — iOS and
Android generate a fresh per-network address so you can't be tracked across Wi-Fi networks. You can spot these:
a randomised (locally-administered) address has the second-lowest bit of its first octet set to 1, which shows
up as a second hex digit of 2, 6, A or E. Such an address
belongs to no real OUI, so it won't resolve to a vendor — that's expected, not a failure. The address you enter
is proxied through our server for the lookup and not stored. For radio devices, the
FCC ID lookup identifies the
certified product; the ASN lookup
covers whole networks.
Frequently asked questions
- A MAC address starts with a 3-byte OUI (Organizationally Unique Identifier) that is registered to a hardware manufacturer. This tool resolves that OUI to the vendor name.
- Just the first three bytes (the OUI). You can paste the full address in any common format — colons, dashes, dots or none — and only the OUI is used.
- They are flags in the first byte. A locally administered address was set by software (not the manufacturer), and a multicast address targets a group rather than one device — neither maps to a vendor.
- The OUI may be unregistered, randomized for privacy (common on phones), or locally administered. Modern devices often randomize their MAC when scanning Wi-Fi.
- Paste the address above; the tool reads its first three bytes — the OUI — and resolves them to the hardware vendor registered with the IEEE. A MAC beginning 3C:5A:B4, for example, returns its manufacturer. Only the OUI is needed, so a partial address (just the first three pairs) works too.
- No. Only the OUI is sent to the vendor database through our server. Nothing is saved.