Which company owns MAC address prefix 78:E9:80?

MAC address prefix 78:E9:80 is registered to RainUs Co.,Ltd in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 78:E9:80 has a network interface built by RainUs Co.,Ltd.

What is the OUI 78:E9:80?

78:E9:80 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to RainUs Co.,Ltd. It covers every address from 78:E9:80:00:00:00 to 78:E9:80:FF:FF:FF, or 16,777,216 addresses in total. It is also written 78-E9-80.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 78:E9:80:00:00:00 that is 78:E9:80 — 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 RainUs Co.,Ltd located?

RainUs Co.,Ltd is listed at E-703, Digital Empire, 16, Deogyeong-daero Suwon-si Gyeonggi-do KR 443-702 in the IEEE OUI registry entry for 78:E9:80. This is the address the organization registered with the IEEE, which may differ from its current operating address.

RainUs Co.,Ltd

MAC address prefix 78:E9:80 is registered to RainUs Co.,Ltd in the IEEE OUI registry. Any device whose MAC address begins with 78:E9:80 has a network interface built by RainUs 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 78:E9:80:00:00:00 to 78:E9:80:FF:FF:FF.

OUI prefix: 78:E9:80
Hyphen form: 78-E9-80
MAC range: 78:E9:80:00:00:00 – 78:E9:80:FF:FF:FF
Addresses in block: 16,777,216
Organization: RainUs Co.,Ltd
Address: E-703, Digital Empire, 16, Deogyeong-daero Suwon-si Gyeonggi-do KR 443-702
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 "RainUs Co.,Ltd"
archived source →
2026-07-17Assigned to "RainUs Co.,Ltd"

Nearby in the registry

The prefixes assigned immediately before and after 78:E9:80:

FAQ

Which company owns MAC address prefix 78:E9:80?: MAC address prefix 78:E9:80 is registered to RainUs Co.,Ltd in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 78:E9:80 has a network interface built by RainUs Co.,Ltd.
What is the OUI 78:E9:80?: 78:E9:80 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to RainUs Co.,Ltd. It covers every address from 78:E9:80:00:00:00 to 78:E9:80:FF:FF:FF, or 16,777,216 addresses in total. It is also written 78-E9-80.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 78:E9:80:00:00:00 that is 78:E9:80 — 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 RainUs Co.,Ltd located?: RainUs Co.,Ltd is listed at E-703, Digital Empire, 16, Deogyeong-daero Suwon-si Gyeonggi-do KR 443-702 in the IEEE OUI registry entry for 78:E9:80. This is the address the organization registered with the IEEE, which may differ from its current operating address.