Hi

I have 2 sheets, one with users and a tool they have been using, and one with a list of unique users, I would like to count how many unique users are using a tool. The sheets are set up like so,

Sheet 1
User Tool (number of uses)
abcdefg 1
hijklmn 5
1234567 1
1234567, abcdefg, opqurst 2
wxyz123 0

Sheet 2 Have they used the tool

abcdefg
hijklmn
1234567
wxyz123
opqurst

So yes, I am trying to count whether or not the unique users have used the tool, this is a simplifed version as my data set runs into the thousands. I was using the countifs function, but that doesnt count properly if theres more than one user in the group. Can anyone help me please?