May 30 2007

# ISNA, ISERROR, and ISBLANK Formula in Excel

Excel has many built-in formulas that will check for errors for you. Were going to take a look at three of those formulas, which are ISNA, ISBLANK and ISERROR. Let’s start by taking a look at the formulas:

ISNA(value)
ISERROR(value)
ISBLANK(value)

Each of these formulas looks at value and evaluatues whether it is #N/A (with ISNA), #Value (with ISERROR), or blank (with ISBLANK).

When You Can Use These Formulas
These formulas come in very handy when you are working with a large group of formulas and need further analysis of the results. Having and #N/A or #Value in your results, as I’m sure you may have experienced, will most likely result in receiving more errors the more that particular result is analyzed. As you’ll see in the examples below, vlookup is a very common formula which will return an #N/A if the lookup value is not found. Or if you try to add a string to a number, the result will return #value.

Examples

Example 1:

Further Explanation
There are other “IS” formulas that can be useful with your projects. We will take a look at these later, as I wanted to get you familiar with some of the main formulas I use every day. The rest of these formulas include:

ISERR(value)
ISLOGICAL(value)
ISNONTEXT(value)
ISNUMBER(value)
ISREF(value)
ISTEXT(value)

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