Which company owns MAC address prefix B8:64:91?

MAC address prefix B8:64:91 is registered to CK Telecom Ltd in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B8:64:91 has a network interface built by CK Telecom Ltd.

What is the OUI B8:64:91?

B8:64:91 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to CK Telecom Ltd. It covers every address from B8:64:91:00:00:00 to B8:64:91:FF:FF:FF, or 16,777,216 addresses in total. It is also written B8-64-91.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in B8:64:91:00:00:00 that is B8:64:91 — 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 CK Telecom Ltd located?

CK Telecom Ltd is listed at Keji Avenue,Heyuan Hi-tech Development Zone Heyuan Guangdong Province CN 517000 in the IEEE OUI registry entry for B8:64:91. This is the address the organization registered with the IEEE, which may differ from its current operating address.

CK Telecom Ltd

MAC address prefix B8:64:91 is registered to CK Telecom Ltd in the IEEE OUI registry. Any device whose MAC address begins with B8:64:91 has a network interface built by CK Telecom 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 B8:64:91:00:00:00 to B8:64:91:FF:FF:FF.

OUI prefix: B8:64:91
Hyphen form: B8-64-91
MAC range: B8:64:91:00:00:00 – B8:64:91:FF:FF:FF
Addresses in block: 16,777,216
Organization: CK Telecom Ltd
Address: Keji Avenue,Heyuan Hi-tech Development Zone Heyuan Guangdong Province CN 517000
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 "CK Telecom Ltd"
archived source →
2026-07-17Assigned to "CK Telecom Ltd"

Nearby in the registry

The prefixes assigned immediately before and after B8:64:91:

FAQ

Which company owns MAC address prefix B8:64:91?: MAC address prefix B8:64:91 is registered to CK Telecom Ltd in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B8:64:91 has a network interface built by CK Telecom Ltd.
What is the OUI B8:64:91?: B8:64:91 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to CK Telecom Ltd. It covers every address from B8:64:91:00:00:00 to B8:64:91:FF:FF:FF, or 16,777,216 addresses in total. It is also written B8-64-91.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in B8:64:91:00:00:00 that is B8:64:91 — 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 CK Telecom Ltd located?: CK Telecom Ltd is listed at Keji Avenue,Heyuan Hi-tech Development Zone Heyuan Guangdong Province CN 517000 in the IEEE OUI registry entry for B8:64:91. This is the address the organization registered with the IEEE, which may differ from its current operating address.