Which company owns MAC address prefix 74:45:CE?

MAC address prefix 74:45:CE is registered to CRESYN in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 74:45:CE has a network interface built by CRESYN.

What is the OUI 74:45:CE?

74:45:CE is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to CRESYN. It covers every address from 74:45:CE:00:00:00 to 74:45:CE:FF:FF:FF, or 16,777,216 addresses in total. It is also written 74-45-CE.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 74:45:CE:00:00:00 that is 74:45:CE — 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 CRESYN located?

CRESYN is listed at 8-22,Jamwon-dong Seoul Seocho-Gu KR #137-902 in the IEEE OUI registry entry for 74:45:CE. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does CRESYN own?

CRESYN holds 5 OUI prefixes in the IEEE registry, of which 74:45:CE is one. A device made by CRESYN could carry a MAC address from any of them.

CRESYN

MAC address prefix 74:45:CE is registered to CRESYN in the IEEE OUI registry. Any device whose MAC address begins with 74:45:CE has a network interface built by CRESYN. 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 74:45:CE:00:00:00 to 74:45:CE:FF:FF:FF.

OUI prefix: 74:45:CE
Hyphen form: 74-45-CE
MAC range: 74:45:CE:00:00:00 – 74:45:CE:FF:FF:FF
Addresses in block: 16,777,216
Organization: CRESYN
Address: 8-22,Jamwon-dong Seoul Seocho-Gu KR #137-902
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 CRESYN

CRESYN holds 5 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.

2019-07-04Assigned to "CRESYN"
archived source →
2026-07-17Assigned to "CRESYN"

Nearby in the registry

The prefixes assigned immediately before and after 74:45:CE:

FAQ

Which company owns MAC address prefix 74:45:CE?: MAC address prefix 74:45:CE is registered to CRESYN in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 74:45:CE has a network interface built by CRESYN.
What is the OUI 74:45:CE?: 74:45:CE is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to CRESYN. It covers every address from 74:45:CE:00:00:00 to 74:45:CE:FF:FF:FF, or 16,777,216 addresses in total. It is also written 74-45-CE.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 74:45:CE:00:00:00 that is 74:45:CE — 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 CRESYN located?: CRESYN is listed at 8-22,Jamwon-dong Seoul Seocho-Gu KR #137-902 in the IEEE OUI registry entry for 74:45:CE. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does CRESYN own?: CRESYN holds 5 OUI prefixes in the IEEE registry, of which 74:45:CE is one. A device made by CRESYN could carry a MAC address from any of them.