Frequently Asked Questions
A MAC (Media Access Control) address is a unique hardware identifier assigned to a device's network interface. It's a 48-bit (6-byte) value typically written as six pairs of hexadecimal digits, e.g., 3C:5A:B4:12:34:56.
An Organizationally Unique Identifier (OUI) is the first portion of a MAC address (24, 28, or 36 bits) assigned by the IEEE Registration Authority to a specific manufacturer. It's what allows tools like MACProbe to identify the vendor behind any device.
MACProbe's database is sourced directly from the official IEEE OUI registry and refreshed on a regular schedule, so results reflect the most current publicly available vendor assignments.
Yes, web-based lookups are free with a reasonable daily usage limit. Developers needing higher volume or programmatic access can use our paid API tiers — see our API Access page for details.
Yes. While MAC addresses are assigned by manufacturers, most operating systems allow software-level MAC address changes ("spoofing"). A lookup result reflects the registered vendor for that address prefix, not necessarily proof of the physical device manufacturer if spoofing has occurred.