Which company owns MAC address prefix C4:57:1F?

MAC address prefix C4:57:1F is registered to June Life Inc in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with C4:57:1F has a network interface built by June Life Inc.

What is the OUI C4:57:1F?

C4:57:1F is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to June Life Inc. It covers every address from C4:57:1F:00:00:00 to C4:57:1F:FF:FF:FF, or 16,777,216 addresses in total. It is also written C4-57-1F.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in C4:57:1F:00:00:00 that is C4:57:1F — 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 June Life Inc located?

June Life Inc is listed at 649 Front Street San Francisco CA US 94111 in the IEEE OUI registry entry for C4:57:1F. This is the address the organization registered with the IEEE, which may differ from its current operating address.

June Life Inc

MAC address prefix C4:57:1F is registered to June Life Inc in the IEEE OUI registry. Any device whose MAC address begins with C4:57:1F has a network interface built by June Life Inc. 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 C4:57:1F:00:00:00 to C4:57:1F:FF:FF:FF.

OUI prefix: C4:57:1F
Hyphen form: C4-57-1F
MAC range: C4:57:1F:00:00:00 – C4:57:1F:FF:FF:FF
Addresses in block: 16,777,216
Organization: June Life Inc
Address: 649 Front Street San Francisco CA US 94111
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.

2017-09-08Assigned to "June Life Inc"
archived source →
2026-07-17Assigned to "June Life Inc"

Nearby in the registry

The prefixes assigned immediately before and after C4:57:1F:

FAQ

Which company owns MAC address prefix C4:57:1F?: MAC address prefix C4:57:1F is registered to June Life Inc in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with C4:57:1F has a network interface built by June Life Inc.
What is the OUI C4:57:1F?: C4:57:1F is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to June Life Inc. It covers every address from C4:57:1F:00:00:00 to C4:57:1F:FF:FF:FF, or 16,777,216 addresses in total. It is also written C4-57-1F.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in C4:57:1F:00:00:00 that is C4:57:1F — 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 June Life Inc located?: June Life Inc is listed at 649 Front Street San Francisco CA US 94111 in the IEEE OUI registry entry for C4:57:1F. This is the address the organization registered with the IEEE, which may differ from its current operating address.