How many users on my account

If you have a Office 2016 perpetual license, you are limited to installation on one computer under one account. You can move it to a different computer on your account.

With Microsoft 365 you would have more options and could share your license with up to five more people. The Personal subscription is still for you only but could be used on multiple devices. The Family subscription allows up to six users each with multiple devices.

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If you install Office 2016 in a Windows 10 "admin" user account, in theory any other Windows 10 users can also sign in to the computer and use it. It worked that way for 2010 and earlier versions, and did work that way for 2016, but I don't know if it still does.

But I have no way of testing. Back in August MS started monkeying around with the way 365 worked.  Before that, you did not have to "sign in" to Office to use it. But after that they started rolling out a (dis)"improvement" that forced users to sign in to Office if the computer was connected to the internet.  A bother.  I don't know if that change was pushed down to 2016 also.  In theory, Office 2016 is also activated and assigned for use by a single email ID, but it wasn't acting that way until the August change.

How can I tell which license I have

File > Account > About Word

How can I tell which license I have