Which company owns MAC address prefix F0:00:7F?

MAC address prefix F0:00:7F is registered to Janz - Contadores de Energia, SA in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with F0:00:7F has a network interface built by Janz - Contadores de Energia, SA.

What is the OUI F0:00:7F?

F0:00:7F is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Janz - Contadores de Energia, SA. It covers every address from F0:00:7F:00:00:00 to F0:00:7F:FF:FF:FF, or 16,777,216 addresses in total. It is also written F0-00-7F.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in F0:00:7F:00:00:00 that is F0:00:7F — 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 Janz - Contadores de Energia, SA located?

Janz - Contadores de Energia, SA is listed at Avenida Infante D. Henrique Lisbon PT 1800-223 in the IEEE OUI registry entry for F0:00:7F. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Janz - Contadores de Energia, SA

MAC address prefix F0:00:7F is registered to Janz - Contadores de Energia, SA in the IEEE OUI registry. Any device whose MAC address begins with F0:00:7F has a network interface built by Janz - Contadores de Energia, SA. 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 F0:00:7F:00:00:00 to F0:00:7F:FF:FF:FF.

OUI prefix: F0:00:7F
Hyphen form: F0-00-7F
MAC range: F0:00:7F:00:00:00 – F0:00:7F:FF:FF:FF
Addresses in block: 16,777,216
Organization: Janz - Contadores de Energia, SA
Address: Avenida Infante D. Henrique Lisbon PT 1800-223
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.

2016-07-29Assigned to "Janz - Contadores de Energia, SA"
archived source →
2026-07-17Assigned to "Janz - Contadores de Energia, SA"

Nearby in the registry

The prefixes assigned immediately before and after F0:00:7F:

FAQ

Which company owns MAC address prefix F0:00:7F?: MAC address prefix F0:00:7F is registered to Janz - Contadores de Energia, SA in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with F0:00:7F has a network interface built by Janz - Contadores de Energia, SA.
What is the OUI F0:00:7F?: F0:00:7F is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Janz - Contadores de Energia, SA. It covers every address from F0:00:7F:00:00:00 to F0:00:7F:FF:FF:FF, or 16,777,216 addresses in total. It is also written F0-00-7F.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in F0:00:7F:00:00:00 that is F0:00:7F — 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 Janz - Contadores de Energia, SA located?: Janz - Contadores de Energia, SA is listed at Avenida Infante D. Henrique Lisbon PT 1800-223 in the IEEE OUI registry entry for F0:00:7F. This is the address the organization registered with the IEEE, which may differ from its current operating address.