IP & Network

MAC Vendor Lookup

Identify hardware manufacturer from a MAC address prefix.

MAC address or OUI Any separator works: colons, dashes, dots, or none. Full MAC or just the first 6 hex characters.
00:1B:63:00:00:00
Vendor
Apple, Inc.
Matched prefix
001B63
Assignment type
MA-L (24 bits, 16M addresses)
Address
1 Infinite Loop Cupertino CA 95014 US

About this tool

Every network interface ships with a 48-bit MAC address. The first 24 bits — the OUI (Organizationally Unique Identifier) — are assigned by IEEE to a specific manufacturer. Our tool takes any MAC (or just the first three bytes) and returns the registered vendor straight from the public IEEE database, along with the registration block size (MA-L, MA-M, MA-S) and the company's registered address.

The IEEE publishes three tiers of allocation: MA-L (Large, 24-bit prefix, 16M addresses), MA-M (Medium, 28-bit, 1M addresses) and MA-S (Small, 36-bit, 4K addresses). Newer small companies and IoT vendors increasingly use MA-M or MA-S blocks — so checking just the first three bytes is no longer always sufficient. Our tool inspects the longer prefix automatically when needed.

When to use this tool

  • Identifying unknown devices on your network. A new MAC showed up in your router's ARP table — vendor lookup tells you whether it is a phone, a printer, a Raspberry Pi, or something unexpected.
  • Inventory audits. Cross-reference MAC tables exported from your switches against a list of approved vendors.
  • Forensics and incident response. Identify the make of devices seen in DHCP logs or packet captures.
  • Hardware spec verification. Confirm a vendor claim — a device sold as "Cisco" with a MAC registered to a different OEM is worth a closer look.

About locally-administered addresses

If the second-least-significant bit of the first byte is set (e.g. 02:, 06:, 0A:, 0E:), the MAC is locally administered — software-generated rather than vendor-burned. Modern phones (iOS, Android, Windows) randomize MACs for Wi-Fi probes, so most "vendor: random/private" entries in your access-point logs are real devices using MAC privacy, not unknown hardware.

Frequently asked questions

What is an OUI?

OUI stands for Organizationally Unique Identifier — the first 24 bits of a MAC address. IEEE assigns each OUI to a specific manufacturer, who is then free to use the remaining 24 bits for individual devices. The OUI lookup table is public and updated nightly; our database is a mirror of the IEEE master file.

Why does my phone's MAC show as "private" or "random"?

Since iOS 14 and Android 10, mobile devices generate a fresh, randomized MAC for every Wi-Fi network they join. The locally-administered bit is set on these addresses (first byte ends in 2, 6, A, or E) and they do not match any IEEE-registered vendor — by design, to defeat tracking across access points.

Are these MA-L, MA-M, MA-S blocks important?

They tell you how many addresses the vendor was allocated. MA-L (3-byte prefix) gives 16 million addresses — typical for large established companies. MA-M (3.5-byte prefix) gives 1 million; MA-S (4.5-byte prefix) gives just 4,096. If a MAC falls into an MA-S block, you need at least the first 4.5 bytes to identify the vendor — looking at only the first three bytes returns the wrong (or no) answer.

Can I look up the model from the MAC?

No — the IEEE only registers manufacturers, not models. A MAC from Apple Inc. could belong to an iPhone, a MacBook, an AirPods case, or a HomePod. Some advanced tooling correlates DHCP fingerprints and probe-request patterns to narrow it down, but the MAC alone is just enough for vendor identification.