MAC Address / OUI Vendor Lookup

Paste a MAC address and identify the manufacturer from its OUI prefix, plus whether it is burned-in or locally administered (randomized). Works in your browser.

Runs locallyComputed in your browser: nothing is sent anywhere

oui.lookup IEEE registry · in this page

The whole IEEE registry is built into this page, so the address you type never leaves your browser. Try 3C:07:54 (Apple), 00:50:56 (VMware), DC:A6:32 (Raspberry Pi) or 24:0A:C4 (ESP32).

What is a MAC address?

A MAC address is the permanent hardware ID built into a device’s network adapter: its Wi-Fi or Ethernet chip. Every phone, laptop, printer, and smart-home gadget has one, and it’s how devices on the same local network find and talk to each other.

It’s written as six pairs of characters, like B8:27:EB:A4:59:D1. The first half is the manufacturer’s code (the OUI) that this tool looks up; the second half is a serial number the maker assigns to that specific device. One handy detail the tool flags: if the second character shows the address is locally administered, it usually means a phone using Wi-Fi privacy, a virtual machine, or a container, not a real hardware vendor. So a “mystery device” on your network is often just a phone protecting its privacy, not an intruder.

How do I find a device’s MAC address?

Every operating system tucks it away in the network settings. The quickest routes:

  • Windows: open Command Prompt, type ipconfig /all, and read the “Physical Address” line for your adapter.
  • macOS: hold Option and click the Wi-Fi icon in the menu bar. The address shows next to “Address”. (Or System Settings → Network → Details → Hardware.)
  • iPhone / iPad: Settings → General → About → Wi-Fi Address.
  • Android: Settings → About phone → Status, or Settings → Network & internet → Wi-Fi → the connected network’s details.
  • Linux: run ip link and look for the link/ether line.
  • Other devices on your network: your Wi-Fi router’s admin page lists the MAC address of everything connected. A good place to paste into this tool.

Learn the background

Where MACs live in a frame and how switches use them: Ethernet & MAC addresses and How switches learn. See them in real captured traffic in Wireshark basics.

Frequently asked questions

What is an OUI?

An Organizationally Unique Identifier: the first 24 bits of a MAC address, assigned to a manufacturer by the IEEE registration authority. Raspberry Pi boards start with B8:27:EB or similar, VMware virtual NICs with 00:50:56, which is why a vendor lookup can identify hardware from a lease table.

Why does my phone show a different MAC on every network?

MAC randomization. Modern iOS and Android generate a random, locally-administered address per Wi-Fi network so you cannot be tracked across locations. The randomized bit is visible in the address itself: this tool flags it as “locally administered”.

Can two devices have the same MAC address?

On the same LAN segment it causes immediate chaos (switches flap between ports), so vendors guarantee uniqueness per OUI block. Across separate networks duplicates are harmless and, with randomization and cloned VMs, increasingly common.