Short answer: A MAC address is a unique hardware ID — six pairs of hex characters like B8:27:EB:A1:B2:C3 — permanently assigned to a device's network hardware at the factory. The first half identifies the manufacturer; the second half identifies the specific unit. Your router uses it to tell every connected device apart.
If you've ever opened your router's connected-devices list, a network scanner, or your phone's WiFi settings, you've seen a MAC address — even if nobody explained what it actually was. Here's what it is, how to read one, how to find yours on any device, and what the manufacturer prefix can (and can't) tell you.
How to read a MAC address
A MAC address is always 12 hex characters, grouped into 6 pairs — for example B8:27:EB:A1:B2:C3. It splits cleanly into two halves:
- First 6 characters (B8:27:EB): the OUI, or Organizationally Unique Identifier — a block the IEEE assigns exclusively to one manufacturer. This half tells you who made the hardware.
- Last 6 characters (A1:B2:C3): a serial number the manufacturer assigns to that specific unit. This half is unique to the individual device, not shared by anything else that vendor makes.
That first half is the useful part if you're trying to identify an unfamiliar device on your network — it's exactly what a MAC address vendor lookup resolves for you, by checking the prefix against the IEEE's public registry.
MAC address vs. IP address — they're not the same thing
These two get mixed up constantly because they both show up in the same "connected devices" list, but they answer different questions:
- MAC address — who: permanent hardware identity, set at the factory, travels with the device wherever it connects.
- IP address — where: a temporary network location your router hands out, reused by different devices over time as they join and leave.
That's also why a MAC address is the more reliable way to identify a specific physical device over time — its IP address can quietly change between reboots, but (barring randomization — more on that below) its MAC address generally doesn't.
How to find your own device's MAC address
Android
Settings → About phone → Status (or Settings → Network & internet → Internet → tap the gear icon next to your WiFi network). Look for "WiFi MAC address."
iPhone / iPad
Settings → General → About, scroll to "Wi-Fi Address." Note that iOS shows a private, randomized address here by default on most networks — see the FAQ below if this doesn't match what your router shows for your phone.
Windows
Open Command Prompt and run ipconfig /all. Look for "Physical Address" under your WiFi or Ethernet adapter.
Mac
System Settings → WiFi → Details (or hold Option and click the WiFi icon in the menu bar for a quick view). Look for "WiFi Address."
What the vendor prefix can — and can't — tell you
Looking up a MAC vendor prefix will reliably tell you:
- Which company manufactured the network chip — useful for spotting an unfamiliar smart plug, camera, or IoT gadget on your router's device list (see our guide to interpreting unfamiliar vendor names like "Espressif" or "Tuya").
It will never tell you:
- The exact product or model — only the chip manufacturer, not the brand printed on the box.
- Who owns the device, or where it's physically located.
- Anything at all, for a device using a randomized private address — modern phones deliberately generate a fake vendor prefix for privacy. See why your router shows ghost or duplicate devices for how to recognize and work around this.
Privacy note: looking up a public vendor prefix is harmless and exactly what it's for. A full MAC address is a different story — it's specific enough to track one physical device, so treat it the way you'd treat any other hardware serial number. ProbeShield's own MAC lookup tool only ever sends the 6-character vendor prefix, truncated in your browser — the rest never leaves it.
Identify every device on your network, not just one at a time
Looking up one MAC address at a time works when you already know what you're checking. If you want to see every device currently on your WiFi — resolved to a manufacturer automatically, no copy-pasting addresses — that's what a full network scan does. See our guide on finding every device connected to your WiFi, or run a scan directly with ProbeShield.
Frequently asked questions
What is a MAC address in simple terms? A MAC (Media Access Control) address is a unique hardware identifier burned into every device's network card — WiFi chip, ethernet port, Bluetooth radio — at the factory. It's how devices recognize each other on a local network, the way a street address identifies a building.
What does a MAC address look like? Six pairs of hex characters (0-9 and A-F), usually separated by colons or hyphens — for example B8:27:EB:A1:B2:C3 or B8-27-EB-A1-B2-C3. Both separators mean the same thing; which one you see just depends on the device or software showing it to you.
What is the difference between a MAC address and an IP address? A MAC address is permanent hardware identity, assigned by the manufacturer and (normally) never changing. An IP address is a temporary network location, assigned by your router and reused by different devices over time — closer to a seat number than a street address.
Can two devices have the same MAC address? Not by design — manufacturers are assigned exclusive blocks of addresses so no two factory-fresh devices collide. In practice a MAC address can be spoofed (deliberately copied) in software, which is why it's an identifier to trust for everyday purposes, not a security guarantee.
Why does my phone's MAC address keep changing? Modern iOS and Android use a randomized, private MAC address by default for each WiFi network you join, specifically so your phone can't be tracked across locations by its hardware address. That's a privacy feature, not a malfunction — see our guide on ghost and duplicate devices for the full explanation.
Is it legal to look up a MAC address vendor? Yes. The vendor prefix is public information published by the IEEE specifically so it can be looked up — that's the entire point of the registry. It only reveals the manufacturer, never anything about the specific device's owner or location.