How to use the mac address format converter
- Paste or type your MAC address into the input field. The mac address converter accepts colons, hyphens, Cisco dots or plain hex.
- Choose your desired output format from the dropdown menu, such as colon-separated or Cisco dotted notation.
- Review the formatted result along with the OUI, NIC split and flag analysis displayed below.
- Copy the converted address directly for use in scripts, network configurations or documentation.
How the mac address format converter works
A MAC address is a 48-bit identifier represented as 12 hexadecimal digits. The mac address format converter strips all separators from the input, validates that exactly 12 hex characters remain, then re-inserts the chosen delimiter.
For example, converting 00:1A:2B:3C:4D:5E to Cisco format involves removing the colons to get 001A2B3C4D5E, then grouping into three blocks of four: 001A.2B3C.4D5E. Converting to plain lowercase simply outputs 001a2b3c4d5e.
Understanding OUI and NIC portions
Every 48-bit MAC address contains two distinct parts. The first 24 bits (three octets) form the Organizationally Unique Identifier, or OUI, which the IEEE assigns to hardware manufacturers. The remaining 24 bits are the Network Interface Controller, or NIC, specific portion assigned by that manufacturer.
| Component | Bits | Hex digits | Example from 00:1A:2B:3C:4D:5E |
|---|---|---|---|
| OUI | 0 to 23 | First 6 | 00:1A:2B |
| NIC | 24 to 47 | Last 6 | 3C:4D:5E |
This mac address formatter separates these automatically so you can identify the vendor block at a glance.
Unicast vs multicast and U/L flags
The first octet of a MAC address carries two important control bits. Bit 0 (the least significant bit) determines whether the frame is unicast or multicast. If bit 0 is 0, the address targets a single interface. If it is 1, the address targets multiple interfaces.
Bit 1 indicates whether the address is universally administered (assigned by IEEE through an OUI) or locally administered (configured manually by a network administrator). A value of 0 means universal, while 1 means local.
For instance, 01:00:5E:00:00:01 has a first octet of 0x01 (binary 00000001). Bit 0 is 1, making it a multicast address. Bit 1 is 0, meaning it is universally administered. This particular prefix belongs to IPv4 multicast mappings.
Common MAC address formats
Different operating systems and network equipment expect different string representations. Using the wrong format can cause configuration errors or script failures.
| Format name | Example | Typical usage |
|---|---|---|
| Colon-separated | 00:1A:2B:3C:4D:5E | Linux, macOS, general networking |
| Hyphen-separated | 00-1A-2B-3C-4D-5E | Windows command line, DHCP logs |
| Cisco dotted | 001A.2B3C.4D5E | Cisco IOS, some switch configs |
| Plain hex | 001A2B3C4D5E | Databases, APIs, internal storage |
This mac address converter handles all four styles in both upper and lower case, covering every common requirement.
Validation rules
A valid input must contain exactly 12 hexadecimal characters after stripping delimiters. Accepted delimiters are colons (:), hyphens (-) and dots (.). Mixed delimiters like 00:1A-2B.3C:4D-5E are rejected because they do not match any standard convention.
Broadcast (FF:FF:FF:FF:FF:FF) is formatted like any other address and flagged with a note. Empty strings, odd-length hex values and non-hexadecimal characters all produce an error message rather than invalid output.
Worked examples
| Example | Input | Result |
|---|---|---|
| Standard EUI-48 | MAC address: 00:1A:2B:3C:4D:5E; Output format: colon-upper | Formatted: 00:1A:2B:3C:4D:5E; OUI: 00:1A:2B; NIC: 3C:4D:5E; Type: Unicast; Administration: Universally administered (UAA); Valid: Yes |
| Cisco format input | MAC address: 001a.2b3c.4d5e; Output format: hyphen-upper | Formatted: 00-1A-2B-3C-4D-5E; OUI: 00:1A:2B; NIC: 3C:4D:5E; Type: Unicast; Administration: Universally administered (UAA); Valid: Yes |
| Multicast address | MAC address: 01:00:5e:00:00:01; Output format: colon-lower | Formatted: 01:00:5e:00:00:01; OUI: 01:00:5E; NIC: 00:00:01; Type: Multicast; Administration: Universally administered (UAA); Valid: Yes |
| Locally administered | MAC address: 02:50:56:C0:00:08; Output format: cisco-upper | Formatted: 0250.56C0.0008; OUI: 02:50:56; NIC: C0:00:08; Type: Unicast; Administration: Locally administered; Valid: Yes |
FAQ
What formats does this mac address converter support?
It supports colon-separated, hyphen-separated, Cisco dotted and plain hex formats, each available in uppercase or lowercase.
Can I paste a Cisco-formatted MAC and get a colon-separated one?
Yes. Enter the Cisco format like 001A.2B3C.4D5E and select the colon-separated output option. The mac address format converter handles the translation instantly.
What is the difference between OUI and NIC?
The OUI is the first 24 bits identifying the manufacturer, while the NIC portion is the last 24 bits identifying the specific device interface.
How do I know if a MAC address is multicast?
Check the least significant bit of the first octet. If it is 1, the address is multicast. This tool displays that flag automatically.
Does this mac address formatter work offline?
Yes. All processing happens in your browser using JavaScript. No data is sent to any server, so it works fully offline once loaded.
Why would I need to change MAC address formats?
Different systems require different formats. Windows often uses hyphens, Linux uses colons, and Cisco devices use dotted notation. Converting ensures compatibility across platforms.