Which company owns MAC address prefix B4:5B:D1?

MAC address prefix B4:5B:D1 is registered to TP-Link Systems Inc. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B4:5B:D1 has a network interface built by TP-Link Systems Inc..

What is the OUI B4:5B:D1?

B4:5B:D1 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to TP-Link Systems Inc.. It covers every address from B4:5B:D1:00:00:00 to B4:5B:D1:FF:FF:FF, or 16,777,216 addresses in total. It is also written B4-5B-D1.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in B4:5B:D1:00:00:00 that is B4:5B:D1 — 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 TP-Link Systems Inc. located?

TP-Link Systems Inc. is listed at 10 Mauchly Irvine CA US 92618 in the IEEE OUI registry entry for B4:5B:D1. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does TP-Link Systems Inc. own?

TP-Link Systems Inc. holds 43 OUI prefixes in the IEEE registry, of which B4:5B:D1 is one. A device made by TP-Link Systems Inc. could carry a MAC address from any of them.

TP-Link Systems Inc.

MAC address prefix B4:5B:D1 is registered to TP-Link Systems Inc. in the IEEE OUI registry. Any device whose MAC address begins with B4:5B:D1 has a network interface built by TP-Link Systems Inc.. 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 B4:5B:D1:00:00:00 to B4:5B:D1:FF:FF:FF.

OUI prefix: B4:5B:D1
Hyphen form: B4-5B-D1
MAC range: B4:5B:D1:00:00:00 – B4:5B:D1:FF:FF:FF
Addresses in block: 16,777,216
Organization: TP-Link Systems Inc.
Address: 10 Mauchly Irvine CA US 92618
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.

Other prefixes from TP-Link Systems Inc.

TP-Link Systems Inc. holds 43 OUI prefixes in total. A device with this exact prefix could just as well carry any of these:

Assignment history (2)

The IEEE registry publishes current state only — this is the change record we've kept since we started tracking it daily.

2025-05-13Assigned to "TP-Link Systems Inc."
archived source →
2026-07-17Assigned to "TP-Link Systems Inc."

Nearby in the registry

The prefixes assigned immediately before and after B4:5B:D1:

FAQ

Which company owns MAC address prefix B4:5B:D1?: MAC address prefix B4:5B:D1 is registered to TP-Link Systems Inc. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B4:5B:D1 has a network interface built by TP-Link Systems Inc..
What is the OUI B4:5B:D1?: B4:5B:D1 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to TP-Link Systems Inc.. It covers every address from B4:5B:D1:00:00:00 to B4:5B:D1:FF:FF:FF, or 16,777,216 addresses in total. It is also written B4-5B-D1.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in B4:5B:D1:00:00:00 that is B4:5B:D1 — 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 TP-Link Systems Inc. located?: TP-Link Systems Inc. is listed at 10 Mauchly Irvine CA US 92618 in the IEEE OUI registry entry for B4:5B:D1. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does TP-Link Systems Inc. own?: TP-Link Systems Inc. holds 43 OUI prefixes in the IEEE registry, of which B4:5B:D1 is one. A device made by TP-Link Systems Inc. could carry a MAC address from any of them.