Which company owns MAC address prefix D4:CF:F9?

MAC address prefix D4:CF:F9 is registered to Shenzhen SEI Robotics Co.,Ltd in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with D4:CF:F9 has a network interface built by Shenzhen SEI Robotics Co.,Ltd.

What is the OUI D4:CF:F9?

D4:CF:F9 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Shenzhen SEI Robotics Co.,Ltd. It covers every address from D4:CF:F9:00:00:00 to D4:CF:F9:FF:FF:FF, or 16,777,216 addresses in total. It is also written D4-CF-F9.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in D4:CF:F9:00:00:00 that is D4:CF:F9 — 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 Shenzhen SEI Robotics Co.,Ltd located?

Shenzhen SEI Robotics Co.,Ltd is listed at 501,Productivity Building A, #5 Hi-Tech Middle 2nd Road Shenzhen Guangdong CN 518057 in the IEEE OUI registry entry for D4:CF:F9. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does Shenzhen SEI Robotics Co.,Ltd own?

Shenzhen SEI Robotics Co.,Ltd holds 3 OUI prefixes in the IEEE registry, of which D4:CF:F9 is one. A device made by Shenzhen SEI Robotics Co.,Ltd could carry a MAC address from any of them.

Shenzhen SEI Robotics Co.,Ltd

MAC address prefix D4:CF:F9 is registered to Shenzhen SEI Robotics Co.,Ltd in the IEEE OUI registry. Any device whose MAC address begins with D4:CF:F9 has a network interface built by Shenzhen SEI Robotics 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 D4:CF:F9:00:00:00 to D4:CF:F9:FF:FF:FF.

OUI prefix: D4:CF:F9
Hyphen form: D4-CF-F9
MAC range: D4:CF:F9:00:00:00 – D4:CF:F9:FF:FF:FF
Addresses in block: 16,777,216
Organization: Shenzhen SEI Robotics Co.,Ltd
Address: 501,Productivity Building A, #5 Hi-Tech Middle 2nd Road Shenzhen Guangdong CN 518057
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 Shenzhen SEI Robotics Co.,Ltd

Shenzhen SEI Robotics Co.,Ltd holds 3 OUI prefixes in total. A device with this exact prefix could just as well carry any of these:

Assignment history (3)

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 "Shenzhen Sen5 Technology Co., Ltd."
archived source →
2020-03-21Renamed from "Shenzhen Sen5 Technology Co., Ltd." to "Shenzhen SEI Robotics Co.,Ltd"
archived source →
2026-07-17Assigned to "Shenzhen SEI Robotics Co.,Ltd"

Nearby in the registry

The prefixes assigned immediately before and after D4:CF:F9:

FAQ

Which company owns MAC address prefix D4:CF:F9?: MAC address prefix D4:CF:F9 is registered to Shenzhen SEI Robotics Co.,Ltd in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with D4:CF:F9 has a network interface built by Shenzhen SEI Robotics Co.,Ltd.
What is the OUI D4:CF:F9?: D4:CF:F9 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Shenzhen SEI Robotics Co.,Ltd. It covers every address from D4:CF:F9:00:00:00 to D4:CF:F9:FF:FF:FF, or 16,777,216 addresses in total. It is also written D4-CF-F9.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in D4:CF:F9:00:00:00 that is D4:CF:F9 — 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 Shenzhen SEI Robotics Co.,Ltd located?: Shenzhen SEI Robotics Co.,Ltd is listed at 501,Productivity Building A, #5 Hi-Tech Middle 2nd Road Shenzhen Guangdong CN 518057 in the IEEE OUI registry entry for D4:CF:F9. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does Shenzhen SEI Robotics Co.,Ltd own?: Shenzhen SEI Robotics Co.,Ltd holds 3 OUI prefixes in the IEEE registry, of which D4:CF:F9 is one. A device made by Shenzhen SEI Robotics Co.,Ltd could carry a MAC address from any of them.