Which company owns MAC address prefix A4:DA:D4?

MAC address prefix A4:DA:D4 is registered to Yamato Denki Co.,Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with A4:DA:D4 has a network interface built by Yamato Denki Co.,Ltd..

What is the OUI A4:DA:D4?

A4:DA:D4 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Yamato Denki Co.,Ltd.. It covers every address from A4:DA:D4:00:00:00 to A4:DA:D4:FF:FF:FF, or 16,777,216 addresses in total. It is also written A4-DA-D4.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in A4:DA:D4:00:00:00 that is A4:DA:D4 — 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 Yamato Denki Co.,Ltd. located?

Yamato Denki Co.,Ltd. is listed at 3-2-14,Koyama Shinagawa-ku,Tokyo JP 142-0062 in the IEEE OUI registry entry for A4:DA:D4. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Yamato Denki Co.,Ltd.

MAC address prefix A4:DA:D4 is registered to Yamato Denki Co.,Ltd. in the IEEE OUI registry. Any device whose MAC address begins with A4:DA:D4 has a network interface built by Yamato Denki Co.,Ltd.. 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 A4:DA:D4:00:00:00 to A4:DA:D4:FF:FF:FF.

OUI prefix: A4:DA:D4
Hyphen form: A4-DA-D4
MAC range: A4:DA:D4:00:00:00 – A4:DA:D4:FF:FF:FF
Addresses in block: 16,777,216
Organization: Yamato Denki Co.,Ltd.
Address: 3-2-14,Koyama Shinagawa-ku,Tokyo JP 142-0062
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.

2021-02-25Assigned to "Yamato Denki Co.,Ltd."
archived source →
2026-07-17Assigned to "Yamato Denki Co.,Ltd."

Nearby in the registry

The prefixes assigned immediately before and after A4:DA:D4:

FAQ

Which company owns MAC address prefix A4:DA:D4?: MAC address prefix A4:DA:D4 is registered to Yamato Denki Co.,Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with A4:DA:D4 has a network interface built by Yamato Denki Co.,Ltd..
What is the OUI A4:DA:D4?: A4:DA:D4 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Yamato Denki Co.,Ltd.. It covers every address from A4:DA:D4:00:00:00 to A4:DA:D4:FF:FF:FF, or 16,777,216 addresses in total. It is also written A4-DA-D4.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in A4:DA:D4:00:00:00 that is A4:DA:D4 — 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 Yamato Denki Co.,Ltd. located?: Yamato Denki Co.,Ltd. is listed at 3-2-14,Koyama Shinagawa-ku,Tokyo JP 142-0062 in the IEEE OUI registry entry for A4:DA:D4. This is the address the organization registered with the IEEE, which may differ from its current operating address.