Which company owns MAC address prefix 5C:E1:A4?

MAC address prefix 5C:E1:A4 is registered to Pleneo in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 5C:E1:A4 has a network interface built by Pleneo.

What is the OUI 5C:E1:A4?

5C:E1:A4 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Pleneo. It covers every address from 5C:E1:A4:00:00:00 to 5C:E1:A4:FF:FF:FF, or 16,777,216 addresses in total. It is also written 5C-E1-A4.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 5C:E1:A4:00:00:00 that is 5C:E1:A4 — 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 Pleneo located?

Pleneo is listed at 9 RAFFLES PLACE #29-05 REPUBLIC PLAZA SG SG 00000 in the IEEE OUI registry entry for 5C:E1:A4. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Pleneo

MAC address prefix 5C:E1:A4 is registered to Pleneo in the IEEE OUI registry. Any device whose MAC address begins with 5C:E1:A4 has a network interface built by Pleneo. 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 5C:E1:A4:00:00:00 to 5C:E1:A4:FF:FF:FF.

OUI prefix: 5C:E1:A4
Hyphen form: 5C-E1-A4
MAC range: 5C:E1:A4:00:00:00 – 5C:E1:A4:FF:FF:FF
Addresses in block: 16,777,216
Organization: Pleneo
Address: 9 RAFFLES PLACE #29-05 REPUBLIC PLAZA SG SG 00000
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.

2025-08-23Assigned to "Pleneo"
archived source →
2026-07-17Assigned to "Pleneo"

Nearby in the registry

The prefixes assigned immediately before and after 5C:E1:A4:

FAQ

Which company owns MAC address prefix 5C:E1:A4?: MAC address prefix 5C:E1:A4 is registered to Pleneo in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 5C:E1:A4 has a network interface built by Pleneo.
What is the OUI 5C:E1:A4?: 5C:E1:A4 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Pleneo. It covers every address from 5C:E1:A4:00:00:00 to 5C:E1:A4:FF:FF:FF, or 16,777,216 addresses in total. It is also written 5C-E1-A4.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 5C:E1:A4:00:00:00 that is 5C:E1:A4 — 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 Pleneo located?: Pleneo is listed at 9 RAFFLES PLACE #29-05 REPUBLIC PLAZA SG SG 00000 in the IEEE OUI registry entry for 5C:E1:A4. This is the address the organization registered with the IEEE, which may differ from its current operating address.