How to use the Excel ISLOGICAL function

Summary

The Excel 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.

Purpose

Test if a value is logical

Return value

A logical value (TRUE or FALSE)

Syntax

=ISLOGICAL (value)

Arguments

value - The value to test as logical.

Usage notes

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

For example, =ISERROR(A1) will return TRUE if A1 contains either TRUE or FALSE.

Note that 1 and 0 (zero) are not evaluated as TRUE and FALSE. However, you can use the AND function to evaluate 1 and 0 and TRUE and FALSE.

Normally, value is supplied as a cell address.

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

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