I think there is a way to do this but having a brain fart at the moment. I have 3 columns, say A-B-C. First 2 are part types and the 3rd list tools. Certain tools go with certain parts indicated by an X in column A or B or both. The tools can be listed multiple times, even for the same part type. I would like to know how many unique tools belong to each part. If I use countif it returns all tools used for a certain part including duplicates. Is there a way to count only unique tools with no duplicates? thanks in advance..