The ISNUMBER function in Excel is a logical function that determines whether a given value is numerical. It is particularly useful in data validation scenarios, where distinguishing between numeric and non-numeric data is critical. This function returns TRUE if the value is a number and FALSE otherwise, aiding in data analysis and formula creation.

Syntax

ISNUMBER(value)

• value: The value you want to test. This can be a direct number, a cell reference, or a formula that returns a number.

Example #1

=ISNUMBER(123)

This function checks if 123 is a number. Result: TRUE.

Example #2

=ISNUMBER(A1)

If cell A1 contains the value ‘150’, this function checks if the content of A1 is a number. Result: TRUE.

Example #3

=ISNUMBER("Hello")

This function evaluates whether the string “Hello” is numeric. Result: FALSE.

Error handling

• VALUE!: This error occurs if the value provided is of an unexpected type, such as a formula that yields an error.

Conclusion

The ISNUMBER function is an essential tool for anyone working with data in Excel, offering a straightforward method to verify if a value is numeric. By effectively distinguishing between numeric values and non-numeric entries, users can enhance their data analysis and ensure accuracy in their calculations.