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MAC Address Vendor Lookup

Find the manufacturer of any network device by its MAC address.

Supports formats: 001A2B3C4D5E, 00:1A:2B:3C:4D:5E, 00-1A-2B-3C-4D-5E

MAC Address Normalizer

Paste any MAC address and convert it between all standard formats instantly, with U/L and I/G bit inspection.

MAC Address Guide

What Is a MAC Address and How Does OUI Lookup Work?

A Media Access Control (MAC) address is a permanently assigned hardware identifier burned into every network interface controller (NIC) at the time of manufacturing. Whether it is the Wi-Fi chip in your smartphone, the Ethernet port on your laptop, or the Bluetooth radio in your smart speaker, each network interface carries a unique MAC address that distinguishes it on a local network. Unlike IP addresses which change based on network topology, MAC addresses are meant to be globally unique and remain fixed to the device hardware for its lifetime.

A standard MAC address is 48 bits long, represented as 12 hexadecimal digits. These 12 characters are divided into two halves. The first six hex characters (24 bits) form the Organizationally Unique Identifier (OUI), which is assigned by the IEEE to device manufacturers. The remaining six hex characters are the network interface controller (NIC) specific portion, uniquely assigned by the manufacturer. When you perform a MAC address vendor lookup, you are querying this OUI portion to determine which company manufactured the network interface.

OUI lookup is an essential troubleshooting technique used by network administrators, IT professionals, and home users alike. When you log into your router's DHCP client list, you will see a table of connected devices identified only by their IP addresses and MAC addresses. Without a MAC address vendor lookup tool, these entries appear as anonymous hexadecimal strings. By looking up the OUI, you can instantly identify that 00:1A:2B belongs to a Cisco device, 3C:07:54 belongs to Apple, or B8:27:EB belongs to a Raspberry Pi. This transforms a meaningless list of numbers into an actionable network inventory that helps identify unknown or unauthorized devices.

The IEEE Registration Authority maintains the official OUI database, which contains over 40,000 registered prefixes covering virtually every hardware manufacturer in the world. Companies like Cisco Systems alone hold hundreds of OUI prefixes due to the sheer volume of network equipment they manufacture. Apple Inc. controls a substantial block for their iPhone, iPad, Mac, and accessory product lines. Intel Corporation's OUI prefixes appear on virtually every motherboard with an integrated Ethernet controller. TP-Link, Netgear, D-Link, and ASUS each control prefixes for their networking hardware. Smartphone manufacturers including Samsung, Xiaomi, and Google hold prefixes for their mobile devices. Even single-board computers like the Raspberry Pi have their own allocated OUI prefix (B8:27:EB), making them easily identifiable on any network.

Modern MAC address lookups support multiple input formats. The IEEE standard uses colon-separated pairs (00:1A:2B:3C:4D:5E), while Microsoft Windows systems typically display MAC addresses with dashes (00-1A-2B-3C-4D-5E). Cisco IOS devices use a dotted format (001A.2B3C.4D5E), and raw format omits separators entirely (001A2B3C4D5E). A good OUI lookup tool accepts all these formats automatically and normalizes them to extract the six-character prefix.

However, there is an important limitation to understand. Modern operating systems including iOS, Android, Windows 11, and macOS now implement privacy-focused MAC randomization features. When a device connects to a Wi-Fi network, it may present a randomly generated MAC address instead of its real hardware address. This prevents network operators and advertisers from tracking devices across different networks. When MAC randomization is active, the OUI prefix will belong to the random address generator, not the actual device manufacturer. For this reason, MAC address vendor lookup is most reliable on wired Ethernet connections and managed network environments where randomization is disabled.

Despite this limitation, MAC address lookup remains one of the most practical tools for network diagnostics. By identifying device vendors from your router's connection table, you can quickly spot unauthorized access points, identify forgotten IoT devices, map network inventory, and troubleshoot IP address conflicts. Our free MAC address vendor lookup tool queries an extensive local database of over 1,500 OUI prefixes covering the most commonly encountered manufacturers from Cisco and Intel to Apple and Samsung. No data is sent to external servers, making it both fast and private.

Whether you are a network engineer managing enterprise infrastructure or a home user checking which devices are connected to your Wi-Fi, a MAC address OUI lookup is the quickest way to turn raw hexadecimal addresses into meaningful device identification.

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Frequently Asked Questions
What is a MAC address vendor lookup?

A MAC address vendor lookup is a tool that identifies the manufacturer of a network device by examining the first six hexadecimal characters of its MAC address. These six characters form the Organizationally Unique Identifier (OUI), which is registered with the IEEE and uniquely assigned to hardware manufacturers. By performing an OUI lookup, you can determine whether a device on your network was made by Cisco, Apple, Intel, Samsung, TP-Link, or any other registered vendor. This is particularly useful when reviewing the list of connected devices on your router, as MAC addresses alone appear as random hex strings without a lookup tool to decode the vendor prefix.

How to lookup MAC address vendor OUI online?

To lookup a MAC address vendor OUI online, simply enter the MAC address into the input field on this page. The tool accepts all common formats including colon-separated (00:1A:2B:3C:4D:5E), dash-separated (00-1A-2B-3C-4D-5E), dotted (001A.2B3C.4D5E), and raw format (001A2B3C4D5E). As you type, the tool automatically extracts the first six hexadecimal characters and searches its built-in database of over 1,500 OUI prefixes. The manufacturer name appears instantly, and the vendor information is displayed with the matching OUI prefix. No sign-up, registration, or personal data is required, and the lookup is performed entirely within your browser, meaning your MAC addresses never leave your device.

Is it possible to trace a MAC address?

A MAC address can only be traced within a local network. MAC addresses operate at Layer 2 (the Data Link Layer) of the OSI model, which means they are not routable across the internet. When data travels between networks, routers strip away the source MAC address at each hop, replacing it with their own. This makes it impossible to trace a device's physical location or identity over the internet using only its MAC address. On your local Wi-Fi or Ethernet network, however, your router keeps a table of all connected MAC addresses, allowing an administrator to identify devices by their vendor (via OUI lookup) and observe their local activity. MAC addresses also do not reveal personal information like your name, address, or browsing history. They only identify the manufacturer of the network interface hardware.

Can I block a MAC address on my Wi-Fi?

Yes, most modern routers allow you to block a specific MAC address using MAC address filtering or access control lists (ACL). This feature lets you create an allowlist (only permit specified devices) or a denylist (block specific devices from connecting). To do this, log into your router's administration panel, find the MAC filtering or wireless access control section, and add the unwanted MAC address to the blocklist. Keep in mind that MAC address filtering is not a strong security measure, because an attacker can spoof or change their MAC address to bypass the filter using widely available software tools. MAC filtering is best used as a convenience feature to manage guest access or prevent casual unauthorized connections. For robust network security, always use WPA3 or WPA2 encryption with a strong passphrase.

How do I lookup my MAC address?

You can find your device's MAC address through the operating system settings. On Windows 10 or 11, open Command Prompt and type ipconfig /all, then look for the Physical Address next to your active network adapter. On macOS, go to System Settings → Network → Advanced → Hardware. On Linux, run ip link or ifconfig in the terminal. On iOS, go to Settings → General → About → Wi-Fi Address. On Android, go to Settings → About Phone → Status → Wi-Fi MAC Address. Once you have the MAC address, enter it into the lookup tool above to identify the manufacturer. Most devices have separate MAC addresses for Wi-Fi and Ethernet, so ensure you check the interface you actively use.