ISNUMBER
TheISNUMBER
formula is used to check if a given value is a number. It returns TRUE if the value is a number and FALSE if it is not. This formula is commonly used in data cleaning and validation to identify and remove nonnumeric values or to ensure that a cell only contains a number.
 How to use
ISNUMBER
formula?  Examples of using
ISNUMBER
formula ISNUMBER
formula not working? Similar formulas to
ISNUMBER
Usage
Use the ISNUMBER
formula with the syntax shown below, it has 1 required parameter:
 value (required):
The value or reference to the cell that you want to check if it is a number.
Examples
Here are a few example use cases that explain how to use theISNUMBER
formula in Google Sheets.
Remove nonnumeric values
You can use the ISNUMBER
formula along with other formulas like IF
, LEN
, and REGEXMATCH
to remove nonnumeric values from a column of data. By applying this formula to each cell in the column, you can identify which cells contain nonnumeric values and then replace them with a blank cell or some other value.
Validate user input
If you have a form or a sheet that requires users to input numbers, you can use the ISNUMBER
formula to validate their input. By applying this formula to the cell that the user inputs data into, you can check if they have entered a number or not. If they have not entered a number, you can display an error message or prompt them to enter a number.
Calculate with only numeric values
By using the ISNUMBER
formula along with other formulas like SUMIF
, AVERAGEIF
, and COUNTIF
, you can calculate with only numeric values in a range. By applying this formula to each cell in the range, you can identify which cells contain numeric values and then use the other formulas to calculate the total, average, or count of only those cells.
Common Mistakes
ISNUMBER
not working? Here are some common mistakes people make when using the ISNUMBER
Google Sheets Formula:
Using text values in the function
The ISNUMBER function only works with numerical values. If you use text values as input, the function will always return FALSE. To correct this, make sure the input is a numerical value.
Not enclosing the input in parentheses
The ISNUMBER function requires the input value to be enclosed in parentheses. Omitting them will result in an error. To correct this, make sure the input is enclosed in parentheses.
Using the wrong data type for the input
The ISNUMBER function only works with numerical values. If you use nonnumerical values as input, the function will always return FALSE. To correct this, make sure the input is a numerical value.
Related Formulas
The following functions are similar to ISNUMBER
or are often used with it in a formula:

ISBLANK
The
ISBLANK
formula is used to check if a cell is empty. It returnsTRUE
if the cell is empty andFALSE
if it contains any data or formula. This formula is commonly used in conditional formatting or data validation rules to ensure a cell is not left empty. 
ISTEXT
The
ISTEXT
function checks whether the value provided is a text string or not. It returns TRUE if the value is text and FALSE if it is any other data type. This function is commonly used when working with data sets that contain text and nontext values. 
ISNONTEXT
The
ISNONTEXT
formula is used to determine if a value is not text. It returnsTRUE
if the value is not text, andFALSE
if the value is text. This formula is commonly used to check if a cell contains text or not. 
IFERROR
The
IFERROR
formula is used to check whether a specified value results in an error or not. If the value results in an error, then it returns a userspecified value instead of the error. This function is commonly used to prevent errors from breaking a formula or to replace error messages with custom messages. 
REGEXMATCH
The
REGEXMATCH
formula searches for a regular expression pattern within a specified text string, and returns a boolean value of TRUE if the pattern is found, and FALSE if it is not found. This formula is commonly used to check if a string matches a certain pattern or to extract specific information from a text string based on a pattern.
Learn More
You can learn more about the ISNUMBER
Google Sheets function on Google Support.