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.

However, Excel's random number functions are volatile, meaning they change constantly. In this article, I'll show you how to generate and fix random numbers and remove duplicates.

When a conditional formatting rule is overkill, use these VBA procedures to highlight duplicates and then remove the highlighting in Microsoft Excel.