Cisco Systems, Inc
MAC address prefix C4:18:FC is registered to Cisco Systems, Inc in the IEEE OUI registry. Any device whose MAC address begins with C4:18:FC has a network interface built by Cisco 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 C4:18:FC:00:00:00 to C4:18:FC:FF:FF:FF.
- OUI prefix
- C4:18:FC
- Hyphen form
- C4-18-FC
- MAC range
- C4:18:FC:00:00:00 – C4:18:FC:FF:FF:FF
- Addresses in block
- 16,777,216
- Organization
- Cisco Systems, Inc
- Address
- 80 West Tasman Drive San Jose CA US 94568
- 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 Cisco Systems, Inc
Cisco Systems, Inc holds 1251 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.
- 2024-06-23Assigned to "Cisco Systems, Inc"archived source →
- 2026-07-17Assigned to "Cisco Systems, Inc"
Nearby in the registry
The prefixes assigned immediately before and after C4:18:FC:
- Apple, Inc.C4:16:8F
- HUAWEI TECHNOLOGIES CO.,LTDC4:16:C8
- Prysm IncC4:16:FA
- Huawei Device Co., Ltd.C4:17:0E
- Hon Hai Precision Ind. Co.,Ltd.C4:17:FE
- Samsung Electronics Co.,LtdC4:18:E9
- Dominion Voting Systems CorporationC4:19:8B
- Telink Semiconductor (Shanghai) Co., Ltd.C4:19:D1
- Qualisys ABC4:19:EC
- Samsung Electronics Co.,LtdC4:1C:07
- JiQiDaoC4:1C:9C
- Vizio, IncC4:1C:FF
FAQ
- Which company owns MAC address prefix C4:18:FC?
- MAC address prefix C4:18:FC is registered to Cisco Systems, Inc in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with C4:18:FC has a network interface built by Cisco Systems, Inc.
- What is the OUI C4:18:FC?
- C4:18:FC is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Cisco Systems, Inc. It covers every address from C4:18:FC:00:00:00 to C4:18:FC:FF:FF:FF, or 16,777,216 addresses in total. It is also written C4-18-FC.
- How do I find the manufacturer of a MAC address?
- Take the first three octets of the address — in C4:18:FC:00:00:00 that is C4:18:FC — 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 Cisco Systems, Inc located?
- Cisco Systems, Inc is listed at 80 West Tasman Drive San Jose CA US 94568 in the IEEE OUI registry entry for C4:18:FC. This is the address the organization registered with the IEEE, which may differ from its current operating address.
- How many MAC prefixes does Cisco Systems, Inc own?
- Cisco Systems, Inc holds 1251 OUI prefixes in the IEEE registry, of which C4:18:FC is one. A device made by Cisco Systems, Inc could carry a MAC address from any of them.