Which company owns MAC address prefix 64:1E:81?

MAC address prefix 64:1E:81 is registered to Dowslake Microsystems in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 64:1E:81 has a network interface built by Dowslake Microsystems.

What is the OUI 64:1E:81?

64:1E:81 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Dowslake Microsystems. It covers every address from 64:1E:81:00:00:00 to 64:1E:81:FF:FF:FF, or 16,777,216 addresses in total. It is also written 64-1E-81.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 64:1E:81:00:00:00 that is 64:1E:81 — 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 Dowslake Microsystems located?

Dowslake Microsystems is listed at 21 High Street, Suite 306 North Andover MA US 01845 in the IEEE OUI registry entry for 64:1E:81. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Dowslake Microsystems

MAC address prefix 64:1E:81 is registered to Dowslake Microsystems in the IEEE OUI registry. Any device whose MAC address begins with 64:1E:81 has a network interface built by Dowslake Microsystems. 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 64:1E:81:00:00:00 to 64:1E:81:FF:FF:FF.

OUI prefix: 64:1E:81
Hyphen form: 64-1E-81
MAC range: 64:1E:81:00:00:00 – 64:1E:81:FF:FF:FF
Addresses in block: 16,777,216
Organization: Dowslake Microsystems
Address: 21 High Street, Suite 306 North Andover MA US 01845
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.

Assignment history (2)

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 "Dowslake Microsystems"
archived source →
2026-07-17Assigned to "Dowslake Microsystems"

Nearby in the registry

The prefixes assigned immediately before and after 64:1E:81:

FAQ

Which company owns MAC address prefix 64:1E:81?: MAC address prefix 64:1E:81 is registered to Dowslake Microsystems in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 64:1E:81 has a network interface built by Dowslake Microsystems.
What is the OUI 64:1E:81?: 64:1E:81 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Dowslake Microsystems. It covers every address from 64:1E:81:00:00:00 to 64:1E:81:FF:FF:FF, or 16,777,216 addresses in total. It is also written 64-1E-81.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 64:1E:81:00:00:00 that is 64:1E:81 — 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 Dowslake Microsystems located?: Dowslake Microsystems is listed at 21 High Street, Suite 306 North Andover MA US 01845 in the IEEE OUI registry entry for 64:1E:81. This is the address the organization registered with the IEEE, which may differ from its current operating address.