COUNTBLANK Function (DAX)
Counts the number of blank cells in a column.
The only argument allowed to this function is a column. You can use columns containing any type of data, but only blank cells are counted. Cells that have the value zero (0) are not counted, as zero is considered a numeric value and not a blank.
Whenever there are no rows to aggregate, the function returns a blank. However, if there are rows, but none of them meet the specified criteria, the function returns 0. Microsoft Excel also returns a zero if no rows are found that meet the conditions.
In other words, if the COUNTBLANK function finds no blanks, the result will be zero, but if there are no rows to check, the result will be blank.
The following example shows how to count the number of rows in the table Reseller that have blank values for BankName.
To count logical values or text, use the COUNTA or COUNTAX functions.