Which company owns MAC address prefix 00:21:AA?

MAC address prefix 00:21:AA is registered to Nokia Danmark A/S in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 00:21:AA has a network interface built by Nokia Danmark A/S.

What is the OUI 00:21:AA?

00:21:AA is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Nokia Danmark A/S. It covers every address from 00:21:AA:00:00:00 to 00:21:AA:FF:FF:FF, or 16,777,216 addresses in total. It is also written 00-21-AA.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 00:21:AA:00:00:00 that is 00:21:AA — 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 Nokia Danmark A/S located?

Nokia Danmark A/S is listed at Frederikskaj Copenhagen V DK DK-1790 in the IEEE OUI registry entry for 00:21:AA. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does Nokia Danmark A/S own?

Nokia Danmark A/S holds 72 OUI prefixes in the IEEE registry, of which 00:21:AA is one. A device made by Nokia Danmark A/S could carry a MAC address from any of them.

Nokia Danmark A/S

MAC address prefix 00:21:AA is registered to Nokia Danmark A/S in the IEEE OUI registry. Any device whose MAC address begins with 00:21:AA has a network interface built by Nokia Danmark A/S. 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 00:21:AA:00:00:00 to 00:21:AA:FF:FF:FF.

OUI prefix: 00:21:AA
Hyphen form: 00-21-AA
MAC range: 00:21:AA:00:00:00 – 00:21:AA:FF:FF:FF
Addresses in block: 16,777,216
Organization: Nokia Danmark A/S
Address: Frederikskaj Copenhagen V DK DK-1790
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 Nokia Danmark A/S

Nokia Danmark A/S holds 72 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.

2016-07-29Assigned to "Nokia Danmark A/S"
archived source →
2026-07-17Assigned to "Nokia Danmark A/S"

Nearby in the registry

The prefixes assigned immediately before and after 00:21:AA:

FAQ

Which company owns MAC address prefix 00:21:AA?: MAC address prefix 00:21:AA is registered to Nokia Danmark A/S in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 00:21:AA has a network interface built by Nokia Danmark A/S.
What is the OUI 00:21:AA?: 00:21:AA is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Nokia Danmark A/S. It covers every address from 00:21:AA:00:00:00 to 00:21:AA:FF:FF:FF, or 16,777,216 addresses in total. It is also written 00-21-AA.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 00:21:AA:00:00:00 that is 00:21:AA — 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 Nokia Danmark A/S located?: Nokia Danmark A/S is listed at Frederikskaj Copenhagen V DK DK-1790 in the IEEE OUI registry entry for 00:21:AA. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does Nokia Danmark A/S own?: Nokia Danmark A/S holds 72 OUI prefixes in the IEEE registry, of which 00:21:AA is one. A device made by Nokia Danmark A/S could carry a MAC address from any of them.