Which company owns MAC address prefix EC:83:D5?

MAC address prefix EC:83:D5 is registered to GIRD Systems Inc in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with EC:83:D5 has a network interface built by GIRD Systems Inc.

What is the OUI EC:83:D5?

EC:83:D5 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to GIRD Systems Inc. It covers every address from EC:83:D5:00:00:00 to EC:83:D5:FF:FF:FF, or 16,777,216 addresses in total. It is also written EC-83-D5.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in EC:83:D5:00:00:00 that is EC:83:D5 — 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 GIRD Systems Inc located?

GIRD Systems Inc is listed at 11260 Chester Road, Ste. 600 Cincinnati OH US 45246 in the IEEE OUI registry entry for EC:83:D5. This is the address the organization registered with the IEEE, which may differ from its current operating address.

GIRD Systems Inc

MAC address prefix EC:83:D5 is registered to GIRD Systems Inc in the IEEE OUI registry. Any device whose MAC address begins with EC:83:D5 has a network interface built by GIRD Systems 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 EC:83:D5:00:00:00 to EC:83:D5:FF:FF:FF.

OUI prefix: EC:83:D5
Hyphen form: EC-83-D5
MAC range: EC:83:D5:00:00:00 – EC:83:D5:FF:FF:FF
Addresses in block: 16,777,216
Organization: GIRD Systems Inc
Address: 11260 Chester Road, Ste. 600 Cincinnati OH US 45246
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.

2018-12-21Assigned to "GIRD Systems Inc"
archived source →
2026-07-17Assigned to "GIRD Systems Inc"

Nearby in the registry

The prefixes assigned immediately before and after EC:83:D5:

FAQ

Which company owns MAC address prefix EC:83:D5?: MAC address prefix EC:83:D5 is registered to GIRD Systems Inc in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with EC:83:D5 has a network interface built by GIRD Systems Inc.
What is the OUI EC:83:D5?: EC:83:D5 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to GIRD Systems Inc. It covers every address from EC:83:D5:00:00:00 to EC:83:D5:FF:FF:FF, or 16,777,216 addresses in total. It is also written EC-83-D5.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in EC:83:D5:00:00:00 that is EC:83:D5 — 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 GIRD Systems Inc located?: GIRD Systems Inc is listed at 11260 Chester Road, Ste. 600 Cincinnati OH US 45246 in the IEEE OUI registry entry for EC:83:D5. This is the address the organization registered with the IEEE, which may differ from its current operating address.