COUNT DAX Function (Aggregation)

Counts the number of rows in the table where the specified column has a non-blank value.

Syntax

COUNT ( <ColumnName> )

Parameter	Attributes	Description
ColumnName		The column that contains the values to be counted.

Scalar A single integer value.

Returns the number of cells in a column that contain a non blank value.

The only argument allowed to this function is a column.

When the function finds no rows that are non-blank, it returns a blank.

COUNT and COUNTA are identical in DAX for all the data types except Boolean. COUNTA can operate on a Boolean data type, whereas COUNT cannot do that.

The COUNT function internally executes COUNTX, without any performance difference.
The following COUNT call:

COUNT ( table[column] )

corresponds to the following COUNTX call:

COUNTX (
    table,
    table[column]
)

Other related functions are:

Contributors: Alberto Ferrari, Marco Russo, Kenneth Barber