Which company owns MAC address prefix B4:01:42?

MAC address prefix B4:01:42 is registered to GCI Science & Technology Co.,LTD in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B4:01:42 has a network interface built by GCI Science & Technology Co.,LTD.

What is the OUI B4:01:42?

B4:01:42 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to GCI Science & Technology Co.,LTD. It covers every address from B4:01:42:00:00:00 to B4:01:42:FF:FF:FF, or 16,777,216 addresses in total. It is also written B4-01-42.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in B4:01:42:00:00:00 that is B4:01:42 — 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 GCI Science & Technology Co.,LTD located?

GCI Science & Technology Co.,LTD is listed at No.381,xingangzhong road , GuangZhou GuangDong CN 510310 in the IEEE OUI registry entry for B4:01:42. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does GCI Science & Technology Co.,LTD own?

GCI Science & Technology Co.,LTD holds 2 OUI prefixes in the IEEE registry, of which B4:01:42 is one. A device made by GCI Science & Technology Co.,LTD could carry a MAC address from any of them.

GCI Science & Technology Co.,LTD

MAC address prefix B4:01:42 is registered to GCI Science & Technology Co.,LTD in the IEEE OUI registry. Any device whose MAC address begins with B4:01:42 has a network interface built by GCI Science & Technology Co.,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 B4:01:42:00:00:00 to B4:01:42:FF:FF:FF.

OUI prefix: B4:01:42
Hyphen form: B4-01-42
MAC range: B4:01:42:00:00:00 – B4:01:42:FF:FF:FF
Addresses in block: 16,777,216
Organization: GCI Science & Technology Co.,LTD
Address: No.381,xingangzhong road , GuangZhou GuangDong CN 510310
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 GCI Science & Technology Co.,LTD

GCI Science & Technology Co.,LTD holds 2 OUI prefixes in total. A device with this exact prefix could just as well carry any of these:

00:1A:7F

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 "GCI Science & Technology Co.,LTD"
archived source →
2026-07-17Assigned to "GCI Science & Technology Co.,LTD"

Nearby in the registry

The prefixes assigned immediately before and after B4:01:42:

FAQ

Which company owns MAC address prefix B4:01:42?: MAC address prefix B4:01:42 is registered to GCI Science & Technology Co.,LTD in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B4:01:42 has a network interface built by GCI Science & Technology Co.,LTD.
What is the OUI B4:01:42?: B4:01:42 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to GCI Science & Technology Co.,LTD. It covers every address from B4:01:42:00:00:00 to B4:01:42:FF:FF:FF, or 16,777,216 addresses in total. It is also written B4-01-42.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in B4:01:42:00:00:00 that is B4:01:42 — 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 GCI Science & Technology Co.,LTD located?: GCI Science & Technology Co.,LTD is listed at No.381,xingangzhong road , GuangZhou GuangDong CN 510310 in the IEEE OUI registry entry for B4:01:42. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does GCI Science & Technology Co.,LTD own?: GCI Science & Technology Co.,LTD holds 2 OUI prefixes in the IEEE registry, of which B4:01:42 is one. A device made by GCI Science & Technology Co.,LTD could carry a MAC address from any of them.