Which company owns MAC address prefix 38:A3:E0?

MAC address prefix 38:A3:E0 is registered to 1Finity Inc in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 38:A3:E0 has a network interface built by 1Finity Inc.

What is the OUI 38:A3:E0?

38:A3:E0 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to 1Finity Inc. It covers every address from 38:A3:E0:00:00:00 to 38:A3:E0:FF:FF:FF, or 16,777,216 addresses in total. It is also written 38-A3-E0.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 38:A3:E0:00:00:00 that is 38:A3:E0 — 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 1Finity Inc located?

1Finity Inc is listed at 4-1-1 Kamikodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa211-8588, Japan Kawasaki Kanagawa JP 211-8588 in the IEEE OUI registry entry for 38:A3:E0. This is the address the organization registered with the IEEE, which may differ from its current operating address.

1Finity Inc

MAC address prefix 38:A3:E0 is registered to 1Finity Inc in the IEEE OUI registry. Any device whose MAC address begins with 38:A3:E0 has a network interface built by 1Finity 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 38:A3:E0:00:00:00 to 38:A3:E0:FF:FF:FF.

OUI prefix: 38:A3:E0
Hyphen form: 38-A3-E0
MAC range: 38:A3:E0:00:00:00 – 38:A3:E0:FF:FF:FF
Addresses in block: 16,777,216
Organization: 1Finity Inc
Address: 4-1-1 Kamikodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa211-8588, Japan Kawasaki Kanagawa JP 211-8588
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.

2026-06-20Assigned to "1Finity Inc"
archived source →
2026-07-17Assigned to "1Finity Inc"

Nearby in the registry

The prefixes assigned immediately before and after 38:A3:E0:

FAQ

Which company owns MAC address prefix 38:A3:E0?: MAC address prefix 38:A3:E0 is registered to 1Finity Inc in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 38:A3:E0 has a network interface built by 1Finity Inc.
What is the OUI 38:A3:E0?: 38:A3:E0 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to 1Finity Inc. It covers every address from 38:A3:E0:00:00:00 to 38:A3:E0:FF:FF:FF, or 16,777,216 addresses in total. It is also written 38-A3-E0.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 38:A3:E0:00:00:00 that is 38:A3:E0 — 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 1Finity Inc located?: 1Finity Inc is listed at 4-1-1 Kamikodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa211-8588, Japan Kawasaki Kanagawa JP 211-8588 in the IEEE OUI registry entry for 38:A3:E0. This is the address the organization registered with the IEEE, which may differ from its current operating address.