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

MAC randomisation, on by default in iOS 14 and later, Android 10 and later, and Windows 10 and later. Each network gets a distinct randomised address so shops and venues cannot track a device across locations by its hardware address. It is a privacy feature and there is no reason to disable it.

Can I find a device owner from a MAC address?

No. The registry maps a prefix to a manufacturer, nothing more. There is no public database linking a MAC address to a person or a location, and the address is visible only on the local network segment anyway.

Does a MAC address travel over the internet?

No. It is a layer 2 identifier, used only within a single network segment. Your router replaces it at every hop. A website cannot see your MAC address, and any site that claims to show it is showing you something else.

Why does the lookup name a chipset maker instead of my laptop brand?

Because the network interface is the component, and its manufacturer registered the block. A laptop with an Intel wireless card returns Intel. Devices with their own silicon, such as recent Apple hardware, return the brand.

How complete is the OUI table?

It is a slice, not the whole registry. The IEEE lists tens of thousands of MA-L blocks, which is far too much to send to a browser, so the build script keeps a fixed number of blocks for each of about 180 vendors that turn up on home and office networks. It is rebuilt monthly and shipped with the page rather than fetched from a server. A prefix that is absent is not proof that no company registered it.

MAC Address Lookup

Paste a MAC address in any format to get the registered vendor, every format variant, and whether the address is randomised.

Paste the address in any format: colons, hyphens, Cisco dots and bare hex all parse. Six hex digits look up the OUI block on their own.

No address parsedPaste a MAC address, or just its first three bytes, to find the registered organisation.

Put an address in the URL as ?q=3C:22:FB:00:00:01 and the whole result above, vendor included, is worked out on the server. With JavaScript on, the IEEE table loads into your browser after your first keystroke and every later lookup happens locally, with nothing sent anywhere.

Accepted formats

All of these parse to the same address:

00:1A:2B:3C:4D:5E
00-1A-2B-3C-4D-5E
001A.2B3C.4D5E
001a2b3c4d5e

You can also enter just the first three bytes to look up a block without a full address.

Reading the two flag bits

The first byte of a MAC address carries two flags in its lowest bits, and they explain most confusing results.

Bit	Value 0	Value 1
Least significant	Unicast, one interface	Multicast, a group
Second least significant	Universally administered, from IEEE	Locally administered, set by software

A hexadecimal second digit of 2, 6, A, or E means the locally administered bit is set. That is the quick way to spot a randomised address by eye: a6:... is random, a4:... is not.

Everything runs locally

The OUI table is bundled with the page and loaded only after your first keystroke, so lookups happen in your browser. MAC addresses are usually copied out of a router’s client list or a packet capture, both of which describe a private network. There is no reason for that to reach a server.

About this tool

The first 24 bits of a hardware address name the organisation that registered the block. Paste a MAC address in any common format and this page reads that identifier against a bundled slice of the IEEE registry. It reports the registered organisation, every format variant, and whether the address is universally or locally administered. The table ships with the page, so nothing is sent to a server.

How to read the result

Organisation name: The company registered with the IEEE for that block, which is the maker of the network chip rather than the brand printed on the case. A block registered to Intel in a machine sold by another company is the normal result.
OUI prefix: The first 24 bits of the address, the block the IEEE assigns, and our table holds MA-L assignments of about 16.7 million addresses each. The smaller MA-M and MA-S blocks subdivide one of those prefixes, so an address inside one still resolves here to the holder of the parent block.
Universally administered: The second-least-significant bit of the first byte is 0, so the manufacturer assigned this address from an IEEE block. It is a factory-assigned address, and the only case where a vendor lookup means anything.
Locally administered or randomised: The second-least-significant bit of the first byte is 1, so software set the address rather than a manufacturer. Modern phones and laptops randomise their Wi-Fi MAC per network, and virtual machines generate addresses the same way, so there is no vendor to find.
Multicast bit: The least significant bit of the first byte is 1, which marks a group address rather than a single interface. 01:00:5e is IPv4 multicast, 33:33 is IPv6 multicast, and ff:ff:ff:ff:ff:ff is broadcast.
Not in the registry: The prefix is absent from our copy of the registry. That happens with a locally administered address, with an unregistered block used by a small manufacturer, and with a very recent assignment that missed the monthly rebuild.

Questions people ask

Why does my phone show a different MAC on every network?: MAC randomisation, on by default in iOS 14 and later, Android 10 and later, and Windows 10 and later. Each network gets a distinct randomised address so shops and venues cannot track a device across locations by its hardware address. It is a privacy feature and there is no reason to disable it.
Can I find a device owner from a MAC address?: No. The registry maps a prefix to a manufacturer, nothing more. There is no public database linking a MAC address to a person or a location, and the address is visible only on the local network segment anyway.
Does a MAC address travel over the internet?: No. It is a layer 2 identifier, used only within a single network segment. Your router replaces it at every hop. A website cannot see your MAC address, and any site that claims to show it is showing you something else.
Why does the lookup name a chipset maker instead of my laptop brand?: Because the network interface is the component, and its manufacturer registered the block. A laptop with an Intel wireless card returns Intel. Devices with their own silicon, such as recent Apple hardware, return the brand.
How complete is the OUI table?: It is a slice, not the whole registry. The IEEE lists tens of thousands of MA-L blocks, which is far too much to send to a browser, so the build script keeps a fixed number of blocks for each of about 180 vendors that turn up on home and office networks. It is rebuilt monthly and shipped with the page rather than fetched from a server. A prefix that is absent is not proof that no company registered it.

Last reviewed 2026-09-05.