MAC Address Generator

Generate random MAC addresses in bulk — up to 100 at a time — in the exact format you need. Choose a separator, upper- or lowercase, and optionally pin a vendor prefix so every generated address belongs to the same OUI block. Useful for seeding test databases, writing network fixtures, filling DHCP lab configs and demoing inventory tools without exposing real hardware identifiers.

How to use it

1. Set Number of addresses with the slider (1–100).
2. Optionally enter a Prefix (OUI) — up to 6 leading bytes to keep fixed.
3. Pick a Separator (colon, hyphen or period) and choose whether the output is uppercase.
4. Click Generate, then copy the list or download it as a .txt file.

Each click produces a fresh set of addresses.

What is a MAC address?

A MAC (Media Access Control) address is the 48-bit hardware identifier burned into a network interface — six bytes, written as twelve hex digits. The first three bytes are the OUI (Organizationally Unique Identifier), assigned by the IEEE to the hardware manufacturer; the last three are chosen by that manufacturer to make each device unique. 00:23:AB:7B:58:99, for example, starts with Cisco's OUI.

What does the prefix option do?

Anything you type into the prefix field is kept, byte for byte; the remaining bytes are randomized. Enter 32:92:d4 and every generated address starts 32:92:D4:…. Separators in the prefix are optional — 32:92:d4, 32-92-d4 and 3292d4 are all read as the same three bytes, and a single hex digit is padded (3:2:d becomes 03:02:0d). Pin a real vendor's OUI when you need the generated data to look like it came from a specific manufacturer.

Which separator should I choose?

Colons (00:23:AB:7B:58:99) are the Unix/Linux convention and the safest default. Hyphens (00-23-AB-7B-58-99) are what Windows displays. The period option separates every byte with a dot, which is handy for tools that expect a dot-delimited list — note that this is not the same as Cisco's three-group 0023.ab7b.5899 notation.

Are these addresses safe to use on a real network?

They are random, so a generated address can collide with a real device's if you assign it on a live network — and if you pin a real vendor prefix, the address will look like genuine hardware from that vendor. Treat the output as test data. If you need addresses that are guaranteed not to clash with any manufacturer's, use a locally administered address: set the second-least-significant bit of the first byte (prefixes like 02, 06, 0A or 0E).

Is my data private?

Yes. Addresses are generated locally in your browser — nothing is sent to a server.