MAC OUI Lookup

Identify device vendor from MAC address OUI prefixes and address bits
This free online mac oui lookup runs in your browser and is part of our Developer Tools collection.

MAC OUI Lookup

Identify the vendor for a MAC address prefix and inspect address type bits.

What this helps with

  • Map discovered devices to likely hardware vendors
  • Practice interpreting OUI and MAC flag bits
  • Assist with inventory and NAC troubleshooting
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Instant In-Browser Execution Runs locally in JavaScript without wait times or server delays.
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100% Privacy & Security Your inputs and files are never stored or logged on remote servers.
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Cross-Device Responsive Fully optimized for mobile smartphones, tablets, and desktop displays.
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100% Free Forever No subscription fees, no signups, and no software installations.

How to Use the Online MAC OUI Lookup

1 Enter MAC Address or Prefix

Input a 48-bit MAC address in any standard format: `00:1A:2B:3C:4D:5E`, `00-1A-2B-3C-4D-5E`, `001A.2B3C.4D5E`, or simply the first 6 hex digits.

2 Query IEEE OUI Database

Click "Lookup Vendor" to search the official IEEE Registration Authority standards database.

3 Inspect Manufacturer & Address Bits

Review the registered Vendor Name, Company Address, and analyze the Unicast/Multicast bit and Universal/Local bit status.

4 Copy Hardware Details

Copy the vendor name and normalized MAC address formats for network asset documentation.

Frequently Asked Questions

Common questions about using this free online mac oui lookup.

What is an Organizationally Unique Identifier (OUI)? ▾
An OUI is the first 24 bits (first 3 octets / 6 hexadecimal digits) of a network device's MAC address, officially assigned to hardware manufacturers (e.g. Apple, Cisco, Intel, Samsung) by the IEEE.
Why does my modern smartphone display a randomized MAC address? ▾
Modern iOS and Android devices use MAC address randomization on public Wi-Fi networks to prevent advertisers and network operators from tracking physical device movements across locations.
How can I tell if a MAC address is locally administered or randomized? ▾
Look at the second hexadecimal digit of the first octet. If it is `2`, `6`, `A`, or `E` (meaning the Universal/Local bit is set to 1), the MAC address is locally administered or randomized rather than a permanent factory hardware OUI.
What is the difference between Unicast and Multicast MAC addresses? ▾
The least significant bit of the first octet indicates whether a frame is destined for a single physical device (Unicast, bit=0) or a group of devices (Multicast, bit=1).

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