Which company owns MAC address prefix 38:77:CD?

MAC address prefix 38:77:CD is registered to KOKUSAI ELECTRIC CORPORATION in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 38:77:CD has a network interface built by KOKUSAI ELECTRIC CORPORATION.

What is the OUI 38:77:CD?

38:77:CD is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to KOKUSAI ELECTRIC CORPORATION. It covers every address from 38:77:CD:00:00:00 to 38:77:CD:FF:FF:FF, or 16,777,216 addresses in total. It is also written 38-77-CD.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 38:77:CD:00:00:00 that is 38:77:CD — 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 KOKUSAI ELECTRIC CORPORATION located?

KOKUSAI ELECTRIC CORPORATION is listed at 2-1 Yasuuchi, Yatsuo-Machi Toyama Toyama Japan JP 939-2393 in the IEEE OUI registry entry for 38:77:CD. This is the address the organization registered with the IEEE, which may differ from its current operating address.

KOKUSAI ELECTRIC CORPORATION

MAC address prefix 38:77:CD is registered to KOKUSAI ELECTRIC CORPORATION in the IEEE OUI registry. Any device whose MAC address begins with 38:77:CD has a network interface built by KOKUSAI ELECTRIC CORPORATION. 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 38:77:CD:00:00:00 to 38:77:CD:FF:FF:FF.

OUI prefix: 38:77:CD
Hyphen form: 38-77-CD
MAC range: 38:77:CD:00:00:00 – 38:77:CD:FF:FF:FF
Addresses in block: 16,777,216
Organization: KOKUSAI ELECTRIC CORPORATION
Address: 2-1 Yasuuchi, Yatsuo-Machi Toyama Toyama Japan JP 939-2393
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.

2024-04-16Assigned to "KOKUSAI ELECTRIC CORPORATION"
archived source →
2026-07-17Assigned to "KOKUSAI ELECTRIC CORPORATION"

Nearby in the registry

The prefixes assigned immediately before and after 38:77:CD:

FAQ

Which company owns MAC address prefix 38:77:CD?: MAC address prefix 38:77:CD is registered to KOKUSAI ELECTRIC CORPORATION in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 38:77:CD has a network interface built by KOKUSAI ELECTRIC CORPORATION.
What is the OUI 38:77:CD?: 38:77:CD is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to KOKUSAI ELECTRIC CORPORATION. It covers every address from 38:77:CD:00:00:00 to 38:77:CD:FF:FF:FF, or 16,777,216 addresses in total. It is also written 38-77-CD.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 38:77:CD:00:00:00 that is 38:77:CD — 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 KOKUSAI ELECTRIC CORPORATION located?: KOKUSAI ELECTRIC CORPORATION is listed at 2-1 Yasuuchi, Yatsuo-Machi Toyama Toyama Japan JP 939-2393 in the IEEE OUI registry entry for 38:77:CD. This is the address the organization registered with the IEEE, which may differ from its current operating address.