Locate which Users have the 'Knowledge User' feature license

Create a Knowledge User Report:
 

1. Go to the Reports tab from the navigation menu.

2. Click New Report and select the Users report in the Administrative Reports category, and click Start Report.

3. Add the Knowledge User field to the columns to see whether each user has the Knowledge User checkbox checked.

Create a Knowledge users list view:
 

1. Navigate to View and Manage Users: From Setup, enter Users in the Quick Find box, then select Users.

2. Follow the corresponding steps provided in Custom Your Data View to create a new user list view with the filter criteria:

Field: Knowledge User
Operator: equals
Value: TRUE
 

Use Developer Console:

1. Open the Developer Console

2. Click Query Editor

3. Copy and paste the following query:

Select Name, ID from User where UserPermissionsKnowledgeUser=true

4. Select the the Execute button to execute the query
 

All users that have the Knowledge User checkbox selected will be listed in the Query Results.

Select a result and click the 'Open Detail Page' button toward the bottom right of the results list to open/view the user record.