2. MacOS "ioreg" command

Please ensure that your YubiKey is connected to your Mac, then open a MacOS "Terminal" window (Applications -> Utilities -> Terminal) and enter the following:

ioreg -l | grep "USB Product Name" | grep -i yubikey

You should see something similar to this:

Example of a Yubikey 5 NFC key

An older Yubikey output might look like this:

Example of a Yubkey v2 key.