What is an OUI in a MAC address?

An Organizationally Unique Identifier (OUI) is the first 24 bits (3 octets) of a MAC address assigned by IEEE to identify the hardware manufacturer (e.g. Apple, Cisco, Intel).

Updated: August 2026 • Verified v1.2

MAC Address Format Converter & OUI Inspector

Internet & NetworkNetwork

Local Browser Execution: Your input is processed locally in your browser and is not sent to UTL servers.

MAC Normalization: Strip non-hex chars ➔ Format into 2-byte or 4-byte delimiter groups; Bit 0: Multicast; Bit 1: Local Admin

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Understanding Your Results

Converts any delimiter format into standard Linux Colon (`00:1A:2B:3C:4D:5E`), Windows Hyphen (`00-1A-2B-3C-4D-5E`), Cisco Dot (`001a.2b3c.4d5e`), and bare hex, with OUI/NIC breakdown and Multicast/Unicast detection.

Practical Guidance & Next Steps

Cisco network equipment requires dot notation with 4-character groups (`001a.2b3c.4d5e`).

What is this?

A network engineering utility that normalizes hardware MAC addresses across operating system conventions.

How does it work?

1. Enter a MAC address in any format. 2. View synchronized Linux, Windows, Cisco, and bare hex notations. 3. Copy desired format or inspect OUI vendor and cast scope in 1 click.