Which company owns MAC address prefix A4:33:D7?

MAC address prefix A4:33:D7 is registered to MitraStar Technology Corp. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with A4:33:D7 has a network interface built by MitraStar Technology Corp..

What is the OUI A4:33:D7?

A4:33:D7 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to MitraStar Technology Corp.. It covers every address from A4:33:D7:00:00:00 to A4:33:D7:FF:FF:FF, or 16,777,216 addresses in total. It is also written A4-33-D7.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in A4:33:D7:00:00:00 that is A4:33:D7 — 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 MitraStar Technology Corp. located?

MitraStar Technology Corp. is listed at No. 6, Innovation Road II, Hsinchu TW 300 in the IEEE OUI registry entry for A4:33:D7. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does MitraStar Technology Corp. own?

MitraStar Technology Corp. holds 20 OUI prefixes in the IEEE registry, of which A4:33:D7 is one. A device made by MitraStar Technology Corp. could carry a MAC address from any of them.

MitraStar Technology Corp.

MAC address prefix A4:33:D7 is registered to MitraStar Technology Corp. in the IEEE OUI registry. Any device whose MAC address begins with A4:33:D7 has a network interface built by MitraStar Technology Corp.. 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 A4:33:D7:00:00:00 to A4:33:D7:FF:FF:FF.

OUI prefix: A4:33:D7
Hyphen form: A4-33-D7
MAC range: A4:33:D7:00:00:00 – A4:33:D7:FF:FF:FF
Addresses in block: 16,777,216
Organization: MitraStar Technology Corp.
Address: No. 6, Innovation Road II, Hsinchu TW 300
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 MitraStar Technology Corp.

MitraStar Technology Corp. holds 20 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.

2018-12-21Assigned to "MitraStar Technology Corp."
archived source →
2026-07-17Assigned to "MitraStar Technology Corp."

Nearby in the registry

The prefixes assigned immediately before and after A4:33:D7:

FAQ

Which company owns MAC address prefix A4:33:D7?: MAC address prefix A4:33:D7 is registered to MitraStar Technology Corp. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with A4:33:D7 has a network interface built by MitraStar Technology Corp..
What is the OUI A4:33:D7?: A4:33:D7 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to MitraStar Technology Corp.. It covers every address from A4:33:D7:00:00:00 to A4:33:D7:FF:FF:FF, or 16,777,216 addresses in total. It is also written A4-33-D7.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in A4:33:D7:00:00:00 that is A4:33:D7 — 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 MitraStar Technology Corp. located?: MitraStar Technology Corp. is listed at No. 6, Innovation Road II, Hsinchu TW 300 in the IEEE OUI registry entry for A4:33:D7. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does MitraStar Technology Corp. own?: MitraStar Technology Corp. holds 20 OUI prefixes in the IEEE registry, of which A4:33:D7 is one. A device made by MitraStar Technology Corp. could carry a MAC address from any of them.