| OUI (vendor prefix) | B8:27:EB |
| Vendor | Raspberry Pi Foundation |
| Colon format | B8:27:EB:12:34:56 |
| Hyphen format | B8-27-EB-12-34-56 |
| Cisco format | b827.eb12.3456 |
| Administration | Universally administered (OUI) |
| Cast | Unicast |
Lookup runs in your browser against a bundled subset of the IEEE OUI registry (common vendors) — nothing is uploaded.
Look up the vendor (OUI) of a MAC address, free. Every network interface has a 48-bit MAC address whose first three bytes are the OUI (Organizationally Unique Identifier) assigned to the manufacturer by the IEEE. This tool matches that OUI prefix to the vendor, normalizes the address into the common formats, and reports the unicast/multicast and universal/local flags — entirely in your browser against a bundled subset of the IEEE registry.
It identifies the manufacturer from a MAC's OUI prefix and decodes its unicast/local bits, so you can attribute a device on your network or spot a locally-administered (often randomized) address. 100% free, no registration, and complete privacy — everything runs locally in your browser, so your data never touches a server.
Matches the first three bytes (the OUI) to the manufacturer for common consumer, networking and virtualisation vendors.
Accepts any input format and shows the colon (00:1a:..), hyphen (00-1a-..) and Cisco-dotted (001a.2b3c..) forms.
Reads the two low bits of the first byte: unicast vs multicast (I/G bit) and universal vs locally-administered (U/L bit).
Lookup runs locally against a bundled OUI subset; nothing you enter is uploaded or stored.
Create random MAC addresses
Identify a device from its UA
IPv4 CIDR breakdown
The first 24 bits of a MAC address are the OUI, a prefix the IEEE assigns to each hardware maker. Looking the OUI up in the IEEE registry returns the vendor. For example B8:27:EB belongs to the Raspberry Pi Foundation.
No. To keep the page fast it bundles a curated subset of the IEEE registry — the most commonly looked-up consumer, networking and virtualisation vendors. For an exhaustive match, consult the full IEEE OUI registry (linked in the references).
If the second-least-significant bit of the first byte is set, the address is locally administered rather than burned-in from an OUI. Modern phones and laptops use randomized, locally-administered MACs for privacy when scanning Wi-Fi.
The least-significant bit of the first byte is the I/G bit: 0 means unicast (a single interface), 1 means multicast (a group). The tool decodes this for you.
No. The lookup runs entirely in your browser against the bundled data; nothing you enter is sent to a server.
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