Which company owns MAC address prefix AC:B1:81?

MAC address prefix AC:B1:81 is registered to Belden Mooresville in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with AC:B1:81 has a network interface built by Belden Mooresville.

What is the OUI AC:B1:81?

AC:B1:81 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Belden Mooresville. It covers every address from AC:B1:81:00:00:00 to AC:B1:81:FF:FF:FF, or 16,777,216 addresses in total. It is also written AC-B1-81.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in AC:B1:81:00:00:00 that is AC:B1:81 — and look that prefix up in the IEEE OUI registry. If the second-lowest bit of the first octet is set, the address is locally administered (a randomized or private MAC), which belongs to no manufacturer and will not resolve; modern phones and laptops use these by default on each network.

Where is Belden Mooresville located?

Belden Mooresville is listed at 1113 N Main St. Mooresville US 28115 in the IEEE OUI registry entry for AC:B1:81. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Belden Mooresville

MAC address prefix AC:B1:81 is registered to Belden Mooresville in the IEEE OUI registry. Any device whose MAC address begins with AC:B1:81 has a network interface built by Belden Mooresville. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address — it covers every MAC from AC:B1:81:00:00:00 to AC:B1:81:FF:FF:FF.

OUI prefix: AC:B1:81
Hyphen form: AC-B1-81
MAC range: AC:B1:81:00:00:00 – AC:B1:81:FF:FF:FF
Addresses in block: 16,777,216
Organization: Belden Mooresville
Address: 1113 N Main St. Mooresville US 28115
Source: IEEE OUI registry

Have a full MAC address? Look it up— we'll also tell you if it's a randomized (private) address rather than a real manufacturer prefix.

Assignment history (2)

The IEEE registry publishes current state only — this is the change record we've kept since we started tracking it daily.

2023-07-11Assigned to "Belden Mooresville"
archived source →
2026-07-17Assigned to "Belden Mooresville"

Nearby in the registry

The prefixes assigned immediately before and after AC:B1:81:

FAQ

Which company owns MAC address prefix AC:B1:81?: MAC address prefix AC:B1:81 is registered to Belden Mooresville in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with AC:B1:81 has a network interface built by Belden Mooresville.
What is the OUI AC:B1:81?: AC:B1:81 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Belden Mooresville. It covers every address from AC:B1:81:00:00:00 to AC:B1:81:FF:FF:FF, or 16,777,216 addresses in total. It is also written AC-B1-81.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in AC:B1:81:00:00:00 that is AC:B1:81 — and look that prefix up in the IEEE OUI registry. If the second-lowest bit of the first octet is set, the address is locally administered (a randomized or private MAC), which belongs to no manufacturer and will not resolve; modern phones and laptops use these by default on each network.
Where is Belden Mooresville located?: Belden Mooresville is listed at 1113 N Main St. Mooresville US 28115 in the IEEE OUI registry entry for AC:B1:81. This is the address the organization registered with the IEEE, which may differ from its current operating address.