If you wish to count the same or duplicate values in a column only once in Excel or the count of occurances of duplicate values, read this article.

Duplicates aren't bad, but you may need to know how many times a value is repeated or how many unique values are in a data range. Here's how to tackle these tasks in Excel.

How can we find duplicate values across multiple columns? For this task, we’ll use two Excel helper formulas: One to concatenate the columns you’re comparing; a second to count the duplicates.