MAC prefix 40:D8:55:11:C: DEUTA-WERKE GmbH

MAC Address Vendor Lookup: Find who made a network card from its MAC address (IEEE registry), spot randomized and virtual machine addresses, and convert formats. Paste many.

The first half of a MAC address is assigned by the IEEE to the company that made the network adapter, so it tells you what a device on your network is: the Apple phone, the HP printer, the VMware VM. Paste one address in any notation, or whole arp -a, ipconfig /all, DHCP lease or switch MAC table output. Phones and newer Windows, macOS and Android versions often use random ("private") addresses, which no vendor owns; those are pointed out. Vendors come from the IEEE Registration Authority's public listings (59,125 assignments, downloaded 2026-10-27).