Which company owns MAC address prefix 38:A5:C9?

MAC address prefix 38:A5:C9 is registered to Tuya Smart Inc. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 38:A5:C9 has a network interface built by Tuya Smart Inc..

What is the OUI 38:A5:C9?

38:A5:C9 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Tuya Smart Inc.. It covers every address from 38:A5:C9:00:00:00 to 38:A5:C9:FF:FF:FF, or 16,777,216 addresses in total. It is also written 38-A5-C9.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 38:A5:C9:00:00:00 that is 38:A5:C9 — 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 Tuya Smart Inc. located?

Tuya Smart Inc. is listed at 160 Greentree Drive, Suite 101 Dover DE US 19904 in the IEEE OUI registry entry for 38:A5:C9. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does Tuya Smart Inc. own?

Tuya Smart Inc. holds 42 OUI prefixes in the IEEE registry, of which 38:A5:C9 is one. A device made by Tuya Smart Inc. could carry a MAC address from any of them.

Tuya Smart Inc.

MAC address prefix 38:A5:C9 is registered to Tuya Smart Inc. in the IEEE OUI registry. Any device whose MAC address begins with 38:A5:C9 has a network interface built by Tuya Smart 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 38:A5:C9:00:00:00 to 38:A5:C9:FF:FF:FF.

OUI prefix: 38:A5:C9
Hyphen form: 38-A5-C9
MAC range: 38:A5:C9:00:00:00 – 38:A5:C9:FF:FF:FF
Addresses in block: 16,777,216
Organization: Tuya Smart Inc.
Address: 160 Greentree Drive, Suite 101 Dover DE US 19904
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 Tuya Smart Inc.

Tuya Smart Inc. holds 42 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 "Tuya Smart Inc."
archived source →
2026-07-17Assigned to "Tuya Smart Inc."

Nearby in the registry

The prefixes assigned immediately before and after 38:A5:C9:

FAQ

Which company owns MAC address prefix 38:A5:C9?: MAC address prefix 38:A5:C9 is registered to Tuya Smart Inc. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 38:A5:C9 has a network interface built by Tuya Smart Inc..
What is the OUI 38:A5:C9?: 38:A5:C9 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Tuya Smart Inc.. It covers every address from 38:A5:C9:00:00:00 to 38:A5:C9:FF:FF:FF, or 16,777,216 addresses in total. It is also written 38-A5-C9.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 38:A5:C9:00:00:00 that is 38:A5:C9 — 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 Tuya Smart Inc. located?: Tuya Smart Inc. is listed at 160 Greentree Drive, Suite 101 Dover DE US 19904 in the IEEE OUI registry entry for 38:A5:C9. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does Tuya Smart Inc. own?: Tuya Smart Inc. holds 42 OUI prefixes in the IEEE registry, of which 38:A5:C9 is one. A device made by Tuya Smart Inc. could carry a MAC address from any of them.