Which company owns MAC address prefix 04:09:A5?

MAC address prefix 04:09:A5 is registered to HFR, Inc. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 04:09:A5 has a network interface built by HFR, Inc..

What is the OUI 04:09:A5?

04:09:A5 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to HFR, Inc.. It covers every address from 04:09:A5:00:00:00 to 04:09:A5:FF:FF:FF, or 16,777,216 addresses in total. It is also written 04-09-A5.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 04:09:A5:00:00:00 that is 04:09:A5 — 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 HFR, Inc. located?

HFR, Inc. is listed at 5F, Hana EZ Tower Sungnam-si Kyunggi-do KR 463-870 in the IEEE OUI registry entry for 04:09:A5. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does HFR, Inc. own?

HFR, Inc. holds 2 OUI prefixes in the IEEE registry, of which 04:09:A5 is one. A device made by HFR, Inc. could carry a MAC address from any of them.

HFR, Inc.

MAC address prefix 04:09:A5 is registered to HFR, Inc. in the IEEE OUI registry. Any device whose MAC address begins with 04:09:A5 has a network interface built by HFR, 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 04:09:A5:00:00:00 to 04:09:A5:FF:FF:FF.

OUI prefix: 04:09:A5
Hyphen form: 04-09-A5
MAC range: 04:09:A5:00:00:00 – 04:09:A5:FF:FF:FF
Addresses in block: 16,777,216
Organization: HFR, Inc.
Address: 5F, Hana EZ Tower Sungnam-si Kyunggi-do KR 463-870
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 HFR, Inc.

HFR, Inc. holds 2 OUI prefixes in total. A device with this exact prefix could just as well carry any of these:

00:23:AA

Assignment history (2)

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

2018-12-21Assigned to "HFR, Inc."
archived source →
2026-07-17Assigned to "HFR, Inc."

Nearby in the registry

The prefixes assigned immediately before and after 04:09:A5:

FAQ

Which company owns MAC address prefix 04:09:A5?: MAC address prefix 04:09:A5 is registered to HFR, Inc. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 04:09:A5 has a network interface built by HFR, Inc..
What is the OUI 04:09:A5?: 04:09:A5 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to HFR, Inc.. It covers every address from 04:09:A5:00:00:00 to 04:09:A5:FF:FF:FF, or 16,777,216 addresses in total. It is also written 04-09-A5.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 04:09:A5:00:00:00 that is 04:09:A5 — 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 HFR, Inc. located?: HFR, Inc. is listed at 5F, Hana EZ Tower Sungnam-si Kyunggi-do KR 463-870 in the IEEE OUI registry entry for 04:09:A5. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does HFR, Inc. own?: HFR, Inc. holds 2 OUI prefixes in the IEEE registry, of which 04:09:A5 is one. A device made by HFR, Inc. could carry a MAC address from any of them.