This guide covers everything you need to know about the Google Sheets ISERROR function, including its definition, syntax, use cases, and how to use it.

## What is the ISERROR Function? How Does It Work?

The ISERROR function in Google Sheets returns TRUE or FALSE based on whether a specific value or expression results in an error. Its primary purpose is to help users identify spreadsheet data or computation errors.

The function evaluates a specified value or expression to check if it results in common spreadsheet errors such as #DIV/0!, #N/A, #NAME?,#NULL!, #NUM!, #VALUE!, and #REF!. If the value or expression does result in an error, ISERROR returns TRUE. Conversely, if there is no error, it returns FALSE.

ISERROR is a comprehensive error-checking function, returning TRUE for any type of error. This contrasts with other functions like ISERR, which returns TRUE for all errors except for #N/A.

ISERROR is typically used in conjunction with conditional statements. This combination allows users to define specific outcomes or actions based on whether a particular value or expression results in an error. For instance, a user might use ISERROR to check if a VLOOKUP function results in an error, and if so, you can return a custom message like “Result not found” rather than an error code.

## ISERROR Syntax

The syntax and arguments for the function are as follows:

**ISERROR(value)**

Here, **‘valu**e’ is the argument for the function. It is the value that you want to test for an error. This could be a cell reference, a formula, or a specific value.

Here are some important usage notes related to the syntax and arguments of the ISERROR function:

- The ‘value’ argument can be a cell reference, a formula, or a specific value. If you use a cell reference or a formula, the ISERROR function will evaluate the cell or the formula first and then check if the result is an error.
- The ISERROR function is case-insensitive. This means that it doesn’t matter if the errors are written in lower case, upper case, or a combination of both.
- If you leave the ‘value’ argument blank, the ISERROR function will return #VALUE! error. This is because the function expects a ‘value’ to test for an error.

## Examples of How to Use the ISERROR Function

Here are some practical examples of how to use the ISERROR function in Google Sheets:

### Example #1: Identifying Errors in a Range of Cells

Let’s say you have a list of calculations in cells A1 to A10 and want to determine if any of these calculations resulted in an error. You can use the ISERROR function to check each cell individually.

In cell B1, you would enter the formula “=ISERROR(A1)”. If cell A1 contains an error, the function will return TRUE. If not, it will return FALSE. You can then drag the formula to cells B2 to B10 to check the rest of the range.

### Example #2: Using ISERROR with IF for Custom Error Messages

You can use the ISERROR function in combination with the IF function to display custom error messages.

For instance, if you have a division operation in cell A1 (like 5/0, which would result in an error), you can use the following formula in cell B1: “=IF(ISERROR(A1), “Error in calculation”, A1)”. If there’s an error in cell A1, Google Sheets will display “Error in calculation”. If there’s no error, it will simply display the result of the calculation in cell A1.

### Example #3: Using ISERROR with VLOOKUP

The VLOOKUP function in Google Sheets often returns an error if it can’t find the lookup value. You can use the ISERROR function to handle this error.

For example, if you’re using VLOOKUP to find a value in a range of cells and you want to return “Not Found” when the lookup value is not in the range, you can use the following formula: “=IF(ISERROR(VLOOKUP(lookup_value, range, index, FALSE)), “Not Found”, VLOOKUP(lookup_value, range, index, FALSE))”.

This formula first checks if the VLOOKUP function returns an error. If it does, it returns “Not Found”. If it doesn’t, it returns the result of the VLOOKUP function.

### Example #4: Using ISERROR with Array Formulas

ISERROR can also be used with array formulas to check for errors in an entire range of cells at once.

For example, if you have a range of cells from A1 to A10 and you want to know if any of them contain errors, you can use the following array formula: “=ARRAYFORMULA(ISERROR(A1:A10))”. This formula will return an array of TRUE or FALSE values, one for each cell in the range. Any cell that contains an error will correspond to a TRUE value in the array.

## Why Is ISERROR Not Working? Troubleshooting Common Errors

If you’re using the ISERROR function in Google Sheets and you find that it’s not working as expected, you might be encountering one of several common errors. Understanding the potential causes of these errors and learning how to troubleshoot them can help you work more effectively with Google Sheets and the ISERROR function.

### #VALUE! Error

**Cause**: The #VALUE! error often appears when the ISERROR function is applied to a cell that contains non-numeric data. This is because the ISERROR function is designed to operate on numeric values and can’t interpret non-numeric data.

**Solution**: To fix this, ensure that the cell or cells to which the ISERROR function is applied contain numeric data. You may need to convert non-numeric data to numeric data before applying the ISERROR function.

### #N/A Error

**Cause**: The #N/A error typically occurs when the ISERROR function is used in a formula that’s trying to find a specific value within a range, but the value isn’t present. This could be because the value doesn’t exist or because there’s a typo or other error in the formula.

**Solution**: To resolve this issue, double-check the formula to ensure that it references the correct range and that the value it’s looking for exists within that range. If the formula is correct and the value doesn’t exist, you may need to adjust your expectations or the data you’re working with.

### #REF! Error

**Cause**: You’ll often see the #REF! error when a formula including the ISERROR function refers to a cell that doesn’t exist. This could be because the cell has been deleted or because the formula is trying to reference a cell outside the valid range of the sheet.

**Solution**: To fix this, adjust the formula to refer to a valid, existing cell. If the cell has been deleted, you may need to recreate it or adjust the formula to refer to a different cell.

### #DIV/0! Error

**Cause**: The #DIV/0! error shows up when a formula with the ISERROR function attempts to divide by zero, which is mathematically undefined.

**Solution**: To resolve this, adjust the formula so it doesn’t attempt to divide by zero. You might need to include additional error-checking logic in your formula to prevent this, or adjust the data you’re working with.

### #NAME? Error

**Cause**: The #NAME? error often happens when a formula contains text that Google Sheets doesn’t recognize. This could be because there’s a typo in the name of a function or because the formula includes text that isn’t enclosed in quotation marks.

**Solution**: Check the formula for typos or other errors to fix this. Ensure that all function names are spelled correctly and that any text that isn’t a function name or a cell reference is enclosed in quotation marks.

### #NUM! Error

**Cause**: The #NUM! error typically occurs when a formula that includes the ISERROR function results in a number that’s too large or too small for Google Sheets to handle.

**Solution**: To resolve this, you’ll need to adjust the formula or the data it’s working with to ensure that the result falls within the range of numbers that Google Sheets can handle.

For more details on the ISERROR function, check out the official documentation at the Google Docs Editors Help Center.