ISNA Excel Function
In this tutorial, you will learn the use of ISNA formula excel. ISNA excel function can be used to know whether a formula process or a data has an #N/A error value or not.
Why do We Need to Learn ISNA Formula Excel?
In the processing process on a spreadsheet, especially in a data lookup process that we do using INDEX MATCH or VLOOKUP formulas, sometimes we get #N/A error values because something that we want to find in our spreadsheet is not found. Often when we get this error value on our processing, we want to mark or change it with another particular value according to our needs so it does not disrupt and can fit with the analysis needs that we do in the spreadsheet.
For a case example of that need in our job, imagine we want to check whether some data are there in the company database or not with the objective to report the ones which are missing so they can be collected later. When we do the data lookup process using spreadsheet formulas, maybe we want to change the #N/A errors that are produced if the data is not there with a particular value so it can be analyzed and counted further. If we need to change them manually without using the help of a spreadsheet function, then, of course, it will be longer to do it, especially if there are much data that we must check to see they are in the company database or not.
To help you mark the error of something not being found when you get it in the spreadsheet, then you can use the ISNA excel function. The ISNA formula excel will help in telling you whether a data or a formula process has an #N/A error value or not. It is very useful if we often deal with the data lookup process in the spreadsheet which often produces #N/A error if the data is not found.
What is ISNA Excel Function?
ISNA excel function is a function with the usage objective to mark a data or a formula process whether it has an #N/A error value. It will give the logic/boolean value of TRUE if yes and FALSE if not. Because the result is a logic value, it is often used as the input part of the IF formula to help the logic evaluation process in it.
ISNA formula excel is one of the IS formula variants besides the others like ISTEXT and ISNUMBER.
Generally, the input of this function can be explained as follows:
=ISNA(value)
Note:
value = the data or formula process that you want to see whether it has an #N/A error value or not
How to Use ISNA Formula Excel?
The following will explain the writing of the ISNA excel function. ISNA formula excel needs one required input which is the data or formula process that you want to check the value of.
Using ISNA Excel Function

Type equal sign ( = ) in the cell where you want to put the result in

Type ISNA (can be with large and small letters) and open bracket sign after =

Input the data or the process that produces the data / cell coordinate where it is located after open bracket sign

Type close bracket sign
 Press Enter

The process is done!
Exercise
After you have understood how to use the ISNA excel function by learning from the above steps, now is the time you deepen your understanding by doing the exercise below!
Download the exercise file and do all of the instructions. Download the answer key file to check your answers if you have finished or if you are confused about how to complete the exercise.
Link for the exercise file:
Download here
Instructions
Use the ISNA formula excel to answer all of the questions! Produce TRUE if the parallel cell content in column 1 is a number and FALSE if it has an #N/A error value!
 Produce V if the parallel cell content in column 2 is a number and X if it has an #N/A error value! Use IF function in excel to help you do it!
 Sum the parallel cell contents in columns 1, 2, and 3. If there is a cell which has the content of #N/A error, then assume it has a 0 value in the sum process! Use IF function also here to help you
Link for the answer key file:
Download here
Additional Notes
 If you want to combine this ISNA formula excel with an IF, then maybe it will be faster to do it using another function which is IFNA. This tips can be considered if you want to directly use the thing that you check with the ISNA excel function as the TRUE result from your IF
 ISNA formula excel cannot be used to check other error types. If you want to check for the other error types too, not only the #N/A type, then you can use ISERROR formula to help you do it