Iserror

Checks if the value given as argument is any type of error. Returns TRUE if it is an error, FALSE if it isn’t.

Iserror syntax

=ISERROR(Value)

Argument Argument description
1Value The value that is checked to be an error.

Returns: TRUE if Value is an error, FALSE if it is not.

Example – Try it for yourself

Spreadsheet editor

Explanation

Calculating the ratio between two things requires dividing the two things. In this case, dividing the number of chairs by the number of people to get the chairs per person ratio. If we have 0 people, we end up dividing by 0. Dividing by 0 is not allowed in mathematics, so Excel shows an error.

Then, we use ISERROR to see if we received an error message. If we did, it gives back the value TRUE. Otherwise, it returns FALSE.

Questions

Is there an ISNOTERROR function?

No, there is not. However, you could create a formula that works that way by using the ISERROR and the NOT function like this: =NOT(ISERROR(A1)).

What error values are checked by ISERROR?

#DIV/0, #N/A, #REF, #VALUE, #NUM, #NAME and #NULL.