Summary

The Excel ISNA function returns TRUE when a cell contains the #N/A error and FALSE for any other value, or any other error type. You can use the ISNA function with the IF function test for #N/A and display a friendly message if the error occurs.

Purpose 

Test for the #N/A error

Return value 

A logical value (TRUE or FALSE)

Syntax

=ISNA(value)
  • value - The value to check if #N/A.

How to use 

The ISNA function returns TRUE when a cell contains the #N/A error and FALSE for any other value, or any other error type. The ISNA function takes one argument, value, which is typically a cell reference.

Examples

If A1 contains the #N/A error, ISNA returns TRUE:

=ISNA(A1) // returns TRUE

ISNA returns FALSE for other values and errors:

=ISNA(100) // returns FALSE
=ISNA(5/0) // returns FALSE

You can use the ISNA function with the IF function test for #N/A and display a friendly message if the error occurs. For example, to display a message if A1 contains #N/A and the value of A1 if not:

=IF(ISNA(A1),"message",A1)

The IFNA function is a more efficient way to trap the #N/A error. See VLOOKUP without NA error for an example.

Return #N/A

To explicitly return the #N/A error in a formula, you can use the NA function:

=NA() // returns #N/A error

The following will return true:

=ISNA(NA()) // returns TRUE

Count #N/A errors

To count cells in a range that contain #N/A errors, you can use the SUMPRODUCT function like this:

=SUMPRODUCT(--ISNA(range))

The double negative coerces the TRUE and FALSE results from ISNA into 1s and 0s and SUMPRODUCT sums the result.

Notes

  • The IFNA function is a more efficient way to trap and handle the #N/A error.
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Dave Bruns

Hi - I'm Dave Bruns, and I run Exceljet with my wife, Lisa. Our goal is to help you work faster in Excel. We create short videos, and clear examples of formulas, functions, pivot tables, conditional formatting, and charts.