Which company owns MAC address prefix 80:CE:B1?

MAC address prefix 80:CE:B1 is registered to Theissen Training Systems GmbH in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 80:CE:B1 has a network interface built by Theissen Training Systems GmbH.

What is the OUI 80:CE:B1?

80:CE:B1 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Theissen Training Systems GmbH. It covers every address from 80:CE:B1:00:00:00 to 80:CE:B1:FF:FF:FF, or 16,777,216 addresses in total. It is also written 80-CE-B1.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 80:CE:B1:00:00:00 that is 80:CE:B1 — 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 Theissen Training Systems GmbH located?

Theissen Training Systems GmbH is listed at Schuchardstrasse 3 Duesseldorf NRW DE 40595 in the IEEE OUI registry entry for 80:CE:B1. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Theissen Training Systems GmbH

MAC address prefix 80:CE:B1 is registered to Theissen Training Systems GmbH in the IEEE OUI registry. Any device whose MAC address begins with 80:CE:B1 has a network interface built by Theissen Training Systems GmbH. 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 80:CE:B1:00:00:00 to 80:CE:B1:FF:FF:FF.

OUI prefix: 80:CE:B1
Hyphen form: 80-CE-B1
MAC range: 80:CE:B1:00:00:00 – 80:CE:B1:FF:FF:FF
Addresses in block: 16,777,216
Organization: Theissen Training Systems GmbH
Address: Schuchardstrasse 3 Duesseldorf NRW DE 40595
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 "Theissen Training Systems GmbH"
archived source →
2026-07-17Assigned to "Theissen Training Systems GmbH"

Nearby in the registry

The prefixes assigned immediately before and after 80:CE:B1:

FAQ

Which company owns MAC address prefix 80:CE:B1?: MAC address prefix 80:CE:B1 is registered to Theissen Training Systems GmbH in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 80:CE:B1 has a network interface built by Theissen Training Systems GmbH.
What is the OUI 80:CE:B1?: 80:CE:B1 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Theissen Training Systems GmbH. It covers every address from 80:CE:B1:00:00:00 to 80:CE:B1:FF:FF:FF, or 16,777,216 addresses in total. It is also written 80-CE-B1.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 80:CE:B1:00:00:00 that is 80:CE:B1 — 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 Theissen Training Systems GmbH located?: Theissen Training Systems GmbH is listed at Schuchardstrasse 3 Duesseldorf NRW DE 40595 in the IEEE OUI registry entry for 80:CE:B1. This is the address the organization registered with the IEEE, which may differ from its current operating address.