# The Excel ISNA Function

Related Functions:
ISERR
ISERROR
Excel #N/A Error

The Excel #N/A error is produced when a value is not available to your formula.

For example, if the Vlookup function is asked to look up the value '10' in a spreadsheet column, but there is no cell containing the value 10, the function will, instead, return the #N/A error.

## Function Description

The Excel ISNA function tests if an initial supplied expression (or value) returns the Excel #N/A Error, and if so, returns TRUE; Otherwise the function returns FALSE.

The syntax of the function is:

ISNA( value )

Where the value argument is the expression or value to be tested.

## Isna Function Examples

The following spreadsheet shows the Excel Isna function, used to test different values and expressions.

Formulas:
A B
1   =ISNA( 536 )
2   =ISNA( "text" )
3   =ISNA( #N/A )
4   =ISNA( 10+5 )
5   =ISNA( VLOOKUP( 10, A1:A7, 1, 0 ) )
6 #N/A =ISNA( A6 )
7 #DIV/0! =ISNA( A7 )
8   =ISNA( A8 )
Results:
A B
1   FALSE
2   FALSE
3   TRUE
4   FALSE
5   TRUE
6 #N/A TRUE
7 #DIV/0! FALSE
8   FALSE

The above examples use different argument types, including:

• Simple values (see cells B1-B3);
• Expressions (see cells B4 & B5);
• Cell references (see cells B6-B8).

Note also that, in the above examples:

• Although the expression in cell A7 is an error, this is not the #N/A error, so the Isna function in cell B7 returns FALSE.
• In cell B5, the Vlookup function cannot find the value '10' in column A of the spreadsheet, and so returns the #N/A error. Therefore, the Isna function returns TRUE.

For further information and examples of the Excel 'Is' functions, see the Microsoft Office website.