🏷️ MAC Address & OUI Vendor Lookup
MAC address lookup against the IEEE OUI registry: identify the manufacturer — Apple, Cisco, Intel, Samsung — behind any address or vendor prefix.
Any separator works, or none. Only the first 6 hex characters are used — the rest identifies the individual device and is not in any public registry.
What MAC Address & OUI Vendor Lookup Does
This tool identifies the manufacturer that registered a MAC address, by looking up its first three bytes in the IEEE registry — 40,017 assignments covering 20,095 organizations.
Only the first six hexadecimal characters matter for that question. They are the Organizationally Unique Identifier, assigned by the IEEE to a company; the remaining six identify an individual device and appear in no public registry anywhere. Entering a full address is fine, and entering just the first six is equally useful.
A lookup that comes back with no vendor is often correct rather than broken. Phones have randomized their MAC addresses by default for several years, and a randomized address is self-generated — there is no manufacturer to find. This tool checks the flag bit that marks those and says so, instead of reporting an unknown vendor.
How to Use MAC Address & OUI Vendor Lookup
- Enter the full MAC address or first 6 characters
- Click Lookup OUI
- View the registered vendor company name, corporate address, and country of origin
Formula Used by MAC Address & OUI Vendor Lookup
What the two flag bits in the first octet mean
bit 0 (value 1) = multicast; bit 1 (value 2) = locally administered
- bit 0
- Set means a group address rather than one device
- bit 1
- Set means the address was assigned by software, not by a manufacturer
Worked example
The first octet of several addresses, tested against both bits.
- B8 = 1011 1000 → neither bit set: globally assigned unicast
- 3C = 0011 1100 → neither bit set: globally assigned unicast
- 02 = 0000 0010 → bit 1 set: locally administered
- 0A = 0000 1010 → bit 1 set: locally administered
- 01 = 0000 0001 → bit 0 set: multicast
Result: Any address whose first octet is 02, 06, 0A, 0E — or any value with the 2 bit set — is self-assigned. That covers every randomized phone MAC, every virtual interface that generates its own, and anything set by hand.
How large a block a company actually receives
device addresses = 2^(48 − prefix bits)
- 48
- Total length of a MAC address in bits
- prefix bits
- How much of the address the IEEE assigns: 24, 28 or 36 bits
Worked example
The three IEEE block sizes.
- MA-L, a 24-bit prefix: 2^24 = 16,777,216 addresses
- MA-M, a 28-bit prefix: 2^20 = 1,048,576 addresses
- MA-S, a 36-bit prefix: 2^12 = 4,096 addresses
Result: A large manufacturer takes MA-L blocks, which is why Apple and Cisco hold hundreds of separate OUIs. Small firms buy MA-M or MA-S, and those cannot be resolved from six characters alone — which is one honest reason a valid address may return nothing here.
Verified Lookups
Run against the bundled IEEE registry on 11 September 2026.
| Prefix | Registered to |
|---|---|
| B8:27:EB | Raspberry Pi Foundation |
| 3C:22:FB | Apple, Inc. |
| 00:1A:11 | Google, Inc. |
| 00:0C:29 | VMware, Inc. |
| 00:15:5D | Microsoft Corporation |
IEEE Registry Blocks
Three sizes, sold at different prices. Only the 24-bit block is resolvable from the first six characters.
| Block | Prefix length | Addresses for the holder | Resolvable here? |
|---|---|---|---|
| MA-L | 24 bits | 16,777,216 | Yes — this is what the tool queries |
| MA-M | 28 bits | 1,048,576 | No — needs 7 hex characters |
| MA-S | 36 bits | 4,096 | No — needs 9 hex characters |
Why a Lookup Returns Nothing
Four distinct reasons, only one of which is a problem with the tool.
| Cause | How to recognize it |
|---|---|
| Randomized device MAC | Locally-administered bit set — first octet 02, 06, 0A, 0E and similar |
| Virtual or manually set interface | Also locally administered; common on VMs and containers |
| MA-M or MA-S assignment | Globally administered, but the company is identified by more than 6 characters |
| Recent assignment | Globally administered and genuinely absent from this registry snapshot |
How to Read Your Result
Your phone does not have one MAC address any more
iOS and Android both generate a different MAC for every network they join, by default, and rotate it periodically. The purpose is to stop shops, airports and advertising networks tracking a device across locations by its hardware address, which was a widespread practice. The practical consequence for anyone looking one up: the address you see in your phone's Wi-Fi settings is usually not the hardware address, is not in any registry, and will differ on the next network. Turning the feature off for a specific network is possible and is usually a bad trade.
MAC filtering is not a security control
Router administration pages still offer MAC allow-lists as a security feature. A MAC address is transmitted in the clear in every frame, including on encrypted Wi-Fi, so anyone within range can read a permitted address, and changing your own MAC to match takes one command on every mainstream operating system. It is a convenience feature for keeping a household tidy. It stops nobody who is trying, and treating it as protection displaces the control that actually matters, which is WPA2 or WPA3 with a strong passphrase.
The vendor is the registrant, not necessarily the maker
The OUI identifies whoever registered the block, which is frequently a component supplier rather than the brand on the box. A laptop may report its wireless chipset vendor, a smart device may report the OEM that actually built it, and a white-label product will show the original manufacturer. Getting an unfamiliar company name is normal and usually means you have found out who really made the part.
It identifies a network interface, not a machine
Every interface has its own address: the Ethernet port and the Wi-Fi radio in the same laptop are different MACs, as is each virtual adapter created by a VM or a container runtime. VMware's 00:0C:29 and 00:50:56 blocks in the table above turn up constantly for exactly that reason. A device with several interfaces has several MACs, and none of them is "the" address of the machine.
Limitations & Accuracy Notes
- MA-L assignments only — 24-bit blocks. Smaller MA-M and MA-S allocations cannot be resolved from the first six characters and will return nothing even though they are validly registered.
- A registry snapshot bundled at build time, so assignments made since the last deploy are missing.
- Blocks the IEEE lists as private are excluded, because the registrant is deliberately withheld.
- Vendor name only. The IEEE registry also carries a postal address, which is omitted here to keep the dataset near a megabyte.
- No device model, product type or firmware identification — an OUI identifies a company, not a product.
- No geolocation. A MAC address carries no location information whatsoever; any service claiming to locate one is using a separate database of observed Wi-Fi networks.
- Cannot tell you whether an address is currently in use, or was ever manufactured at all.
Frequently Asked Questions
What is an OUI in a MAC address?
What MAC address formats are supported?
Why does my phone's MAC address return no vendor?
How can I tell a randomized address by looking at it?
Is MAC filtering a useful security measure?
Why is the vendor a company I have never heard of?
Can a MAC address tell me where a device is?
Why does a valid address sometimes return nothing?
References & Further Reading
- IEEE Registration Authority — MAC Address Block Large (MA-L) public listing — The authoritative registry this tool bundles: 40,127 rows at time of build, from which 40,017 non-private assignments across 20,095 organizations were extracted
- IEEE Registration Authority — The body that assigns MA-L, MA-M and MA-S blocks, and the source of the block-size definitions above