How does the ISLOGICAL function (DAX) work?

ISLOGICAL function (DAX) checks if a value (TRUE or FALSE) is a rational value and returns TRUE or FALSE. It is part of a group of functions called the IS functions, usually used to evaluate the outcome of error formulas.

ISLOGICAL Formula Syntax

ISINSCOPE (<columnName>)

How do you use the ISLOGICAL function?

ISLOGICAL function returns TRUE when a cell contains the logical values TRUE or FALSE, and returns FALSE for cells that contain any other value, including empty cells.

Considerations when using the ISLOGICAL function

ISLOGICAL is part of a group of functions called the IS functions, which are often used to test the result of formulas for errors.

Use the ISLOGICAL function to check if a value is logical. ISLOGICAL will return TRUE when a value is TRUE or FALSE.

Formula examples using the ISLOGICAL function

//RETURNS: Is Boolean type or Logical  
=IF(ISLOGICAL(true), "Is Boolean type or Logical", "Is different type")  
  
//RETURNS: Is Boolean type or Logical  
=IF(ISLOGICAL(false), "Is Boolean type or Logical", "Is different type")  
  
//RETURNS: Is different type  
=IF(ISLOGICAL(25), "Is Boolean type or Logical", "Is different type")