Which company owns MAC address prefix A4:5D:5E?

MAC address prefix A4:5D:5E is registered to Wilk Elektronik S.A. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with A4:5D:5E has a network interface built by Wilk Elektronik S.A..

What is the OUI A4:5D:5E?

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

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in A4:5D:5E:00:00:00 that is A4:5D:5E — 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 Wilk Elektronik S.A. located?

Wilk Elektronik S.A. is listed at Mikolowska 42 Laziska Gorne Slaskie PL 43-173 in the IEEE OUI registry entry for A4:5D:5E. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Wilk Elektronik S.A.

MAC address prefix A4:5D:5E is registered to Wilk Elektronik S.A. in the IEEE OUI registry. Any device whose MAC address begins with A4:5D:5E has a network interface built by Wilk Elektronik S.A.. 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 A4:5D:5E:00:00:00 to A4:5D:5E:FF:FF:FF.

OUI prefix: A4:5D:5E
Hyphen form: A4-5D-5E
MAC range: A4:5D:5E:00:00:00 – A4:5D:5E:FF:FF:FF
Addresses in block: 16,777,216
Organization: Wilk Elektronik S.A.
Address: Mikolowska 42 Laziska Gorne Slaskie PL 43-173
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.

2023-07-11Assigned to "Wilk Elektronik S.A."
archived source →
2026-07-17Assigned to "Wilk Elektronik S.A."

Nearby in the registry

The prefixes assigned immediately before and after A4:5D:5E:

FAQ

Which company owns MAC address prefix A4:5D:5E?: MAC address prefix A4:5D:5E is registered to Wilk Elektronik S.A. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with A4:5D:5E has a network interface built by Wilk Elektronik S.A..
What is the OUI A4:5D:5E?: A4:5D:5E is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Wilk Elektronik S.A.. It covers every address from A4:5D:5E:00:00:00 to A4:5D:5E:FF:FF:FF, or 16,777,216 addresses in total. It is also written A4-5D-5E.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in A4:5D:5E:00:00:00 that is A4:5D:5E — 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 Wilk Elektronik S.A. located?: Wilk Elektronik S.A. is listed at Mikolowska 42 Laziska Gorne Slaskie PL 43-173 in the IEEE OUI registry entry for A4:5D:5E. This is the address the organization registered with the IEEE, which may differ from its current operating address.