Which company owns MAC address prefix 5C:D6:1F?

MAC address prefix 5C:D6:1F is registered to Qardio, Inc in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 5C:D6:1F has a network interface built by Qardio, Inc.

What is the OUI 5C:D6:1F?

5C:D6:1F is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Qardio, Inc. It covers every address from 5C:D6:1F:00:00:00 to 5C:D6:1F:FF:FF:FF, or 16,777,216 addresses in total. It is also written 5C-D6-1F.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 5C:D6:1F:00:00:00 that is 5C:D6:1F — 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 Qardio, Inc located?

Qardio, Inc is listed at 340 S Lemon Ave #1104F Walnut California US 91789 in the IEEE OUI registry entry for 5C:D6:1F. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Qardio, Inc

MAC address prefix 5C:D6:1F is registered to Qardio, Inc in the IEEE OUI registry. Any device whose MAC address begins with 5C:D6:1F has a network interface built by Qardio, 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 5C:D6:1F:00:00:00 to 5C:D6:1F:FF:FF:FF.

OUI prefix: 5C:D6:1F
Hyphen form: 5C-D6-1F
MAC range: 5C:D6:1F:00:00:00 – 5C:D6:1F:FF:FF:FF
Addresses in block: 16,777,216
Organization: Qardio, Inc
Address: 340 S Lemon Ave #1104F Walnut California US 91789
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 "Qardio, Inc"
archived source →
2026-07-17Assigned to "Qardio, Inc"

Nearby in the registry

The prefixes assigned immediately before and after 5C:D6:1F:

FAQ

Which company owns MAC address prefix 5C:D6:1F?: MAC address prefix 5C:D6:1F is registered to Qardio, Inc in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 5C:D6:1F has a network interface built by Qardio, Inc.
What is the OUI 5C:D6:1F?: 5C:D6:1F is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Qardio, Inc. It covers every address from 5C:D6:1F:00:00:00 to 5C:D6:1F:FF:FF:FF, or 16,777,216 addresses in total. It is also written 5C-D6-1F.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 5C:D6:1F:00:00:00 that is 5C:D6:1F — 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 Qardio, Inc located?: Qardio, Inc is listed at 340 S Lemon Ave #1104F Walnut California US 91789 in the IEEE OUI registry entry for 5C:D6:1F. This is the address the organization registered with the IEEE, which may differ from its current operating address.