Author: Oscar Cronquist Article last updated on April 17, 2018

The ISLOGICAL function returns TRUE if value is boolean. A boolean value is either TRUE or FALSE.

Formula in cell C3:


Excel Function Syntax



value Required. The value you want to check for a boolean value.


Note that Excel interprets a number not equal to 0 (zero) as TRUE and 0 (zero) as FALSE, for example, in a IF function. However, the ISLOGICAL function does not.

The ISLOGICAL function is very useful to identify error values in arrays. Most Excel functions return the same error value, however, this function returns FALSE if it encounters an error.