IS functions

This article describes the formula syntax and usage of the IS functions (function: A prewritten formula that takes a value or values, performs an operation, and returns a value or values. Use functions to simplify and shorten formulas on a worksheet, especially those that perform lengthy or complex calculations.) in Microsoft Excel.


Each of these functions, referred to collectively as the IS functions, checks the specified value and returns TRUE or FALSE depending on the outcome. For example, the ISBLANK function returns the logical value TRUE if the value argument is a reference to an empty cell; otherwise it returns FALSE.

You can use an IS function to get information about a value before performing a calculation or other action with it. For example, you can use the ISERROR function in conjunction with the IF function to perform a different action if an error occurs:

=IF(ISERROR(A1), "An error occurred.", A1 * 2)

This formula checks to see if an error condition exists in A1. If so, the IF function returns the message "An error occurred." If no error exists, the IF function performs the calculation A1*2.



The IS function syntax has the following argument (argument: A value that provides information to an action, an event, a method, a property, a function, or a procedure.):

  • value    Required. The value that you want tested. The value argument can be a blank (empty cell), error, logical value, text, number, or reference value, or a name referring to any of these.
Function Returns TRUE if
ISBLANK Value refers to an empty cell.
ISERR Value refers to any error value except #N/A.
ISERROR Value refers to any error value (#N/A, #VALUE!, #REF!, #DIV/0!, #NUM!, #NAME?, or #NULL!).
ISLOGICAL Value refers to a logical value.
ISNA Value refers to the #N/A (value not available) error value.
ISNONTEXT Value refers to any item that is not text. (Note that this function returns TRUE if the value refers to a blank cell.)
ISNUMBER Value refers to a number.
ISREF Value refers to a reference.
ISTEXT Value refers to text.


  • The value arguments of the IS functions are not converted. Any numeric values that are enclosed in double quotation marks are treated as text. For example, in most other functions where a number is required, the text value "19" is converted to the number 19. However, in the formula ISNUMBER("19"), "19" is not converted from a text value to a number value, and the ISNUMBER function returns FALSE.
  • The IS functions are useful in formulas for testing the outcome of a calculation. When combined with the IF function, these functions provide a method for locating errors in formulas (see the following examples).


Example 1

Use the embedded workbook shown here to work with examples of this function. You can inspect and change existing formulas, enter your own formulas, and read further information about how the function works.

These examples use several of the IS functions to check the contents of the specified cell or a value specified as an argument.

To work in-depth with this workbook, you can download it to your computer and open it in Excel. For more information, see the article. Download an embedded workbook from OneDrive and open it on your computer.

Example 2

These examples use several of the IS functions to check the contents of the specified cell.

Applies to:
Excel 2010, Excel Web App, SharePoint Online for enterprises, SharePoint Online for professionals and small businesses