MAC Address & OUI Lookup

Free MAC address and OUI lookup tool. Identify device manufacturers and network hardware vendors from MAC prefixes locally with zero server logs.

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Browser-Native Local ExecutionProcessed locally inside browser memory with zero server storage.

Instant Real-Time ExecutionZero latency data manipulation powered by Web APIs.

Free & UnrestrictedNo accounts, subscriptions, or daily usage limits.

Technical Overview: How MAC Address & OUI Lookup Works

The MAC Address & OUI Lookup searches the IEEE Organizationally Unique Identifier (OUI) registry to identify device manufacturers, analyzes bit-level flags (I/G, U/L), detects randomized private MACs, converts across 6 notations (including EUI-64), and supports reverse vendor search.

Parses 48-bit MAC addresses across IEEE colon, Windows hyphen, Cisco dot, space, raw hex, and IPv6 EUI-64 SLAAC formats. Inspects the least-significant bits of the first octet to identify Unicast vs Multicast (I/G bit) and Universally vs Locally Administered (U/L bit). Matches prefixes against a bundled IEEE OUI database covering 200+ major manufacturers.

Practical Examples & Usage

Looking up Apple Hardware MAC Address

Input:MAC: 3C:06:30:11:22:33

Output:

OUI: 3C-06-30 | Vendor: Apple, Inc. | Address Type: Unicast, Universally Administered (UAA) | Formats: 3c:06:30:11:22:33 / 3c06.3011.2233

Matches the first 3 octets (3C:06:30) to Apple Inc. in the official IEEE OUI database and confirms global hardware assignment.

Real-World Applications & Use Cases

Identifying unknown devices, IoT hardware, and rogue endpoints connected to local Wi-Fi and corporate networks.
Detecting modern smartphone randomized private Wi-Fi MAC addresses during network access audits.
Troubleshooting network switch port mappings and DHCP client leases during IT infrastructure audits.
Calculating IPv6 Stateless Address Autoconfiguration (SLAAC) EUI-64 modified interface identifiers from MAC addresses.

How to use MAC Address & OUI Lookup

Enter any MAC address or 24-bit OUI prefix (e.g. 00:1A:2B:3C:4D:5E, 00-1A-2B, or raw hex).
Identify the physical hardware manufacturer (Apple, Cisco, Intel, Samsung, Raspberry Pi, etc.).
View normalized representations: Colon (IEEE), Hyphen (Windows), Cisco Dot, and IPv6 EUI-64.
Check bit-level analysis: Unicast vs Multicast (I/G bit) and UAA vs LAA (Locally Administered).
Switch to "Search OUIs by Vendor" to explore registered manufacturer prefixes directly.

Edge Cases & Limitations

•Modern smartphones (iOS Private Wi-Fi, Android MAC Randomization, Windows Random Hardware Addresses) use Locally Administered Addresses (LAA) that do not map to manufacturer OUIs.
•Virtual machines (VMware, VirtualBox, Hyper-V) use specific virtual OUI blocks rather than physical hardware vendors.
•IEEE OUI-36 (MA-S) and OUI-28 (MA-M) smaller block assignments may resolve to the parent block holder in basic 24-bit lookups.

Recommended Best Practices

•Check whether the "Locally Administered" bit is set if a device MAC does not resolve to an expected hardware vendor.
•Standardize on colon notation (XX:XX:XX:XX:XX:XX) for network documentation, firewall rules, and router configuration.
•Use 802.1X enterprise network security and certificate authentication rather than static MAC filtering alone.

Privacy & Data Handling: How MAC Address & OUI Lookup Treats Your Inputs

Processing Runtime

All text transformations, mathematical calculations, code formatting, and asset conversions execute locally inside your web browser sandbox.

Memory & Storage

Processed text and parameters are handled in browser memory. Optional configuration preferences (like dark/light theme) are stored in your browser local storage for convenience.

Network Transmission

No tool inputs or processed results are uploaded or logged to Outlivo servers.

For complete transparency on data isolation and client sandboxing, visit our Privacy Policy or contact us via the Contact Center.

Frequently Asked Questions

What is an OUI in a MAC address?

OUI stands for Organizationally Unique Identifier. The first 3 bytes (24 bits) of a MAC address are assigned by the IEEE Standards Association to specific hardware manufacturers like Apple, Cisco, Intel, or Dell.

Why does my smartphone MAC address show as "Locally Administered"?

Modern mobile devices (iOS Private Wi-Fi, Android MAC Randomization, Windows Random Hardware Addresses) automatically generate randomized MAC addresses with the Locally Administered bit (bit 1) enabled to prevent cross-network Wi-Fi tracking.

What is the difference between EUI-48 and EUI-64?

EUI-48 is standard 48-bit MAC addressing. EUI-64 expands it to a 64-bit interface identifier by inverting the U/L bit and inserting 0xFFFE into the middle, utilized in IPv6 Stateless Address Autoconfiguration (SLAAC).

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