ISNUMBER: Google Sheets Formulas Explained

Hello there! Are you looking for a way to make your life easier when it comes to working with numbers in Google Sheets? Well, you've come to the right place because I'm about to introduce you to one of the most useful formulas in Sheets: ISNUMBER.

Now, you may be asking yourself, "What the heck does ISNUMBER do?" Don't worry, I'm here to explain it all.


In simple terms, ISNUMBER is a function in Google Sheets that checks whether a value is a number or not. It returns true if the cell contains a number, and false if it does not.

But wait, there's more! ISNUMBER doesn't just work on single cells. You can apply it to entire columns of data by using an array formula.


To use ISNUMBER, simply type "=ISNUMBER(cell reference)" into the cell where you want the result to appear. Replace "cell reference" with the cell you want to check.

For example, let's say you have a list of values in cells A1 through A5 and you want to check which ones are numbers. You would type "=ISNUMBER(A1)" into cell B1 and then copy and paste that formula into cells B2 through B5.

Now, cells B1 through B5 will display "TRUE" or "FALSE" depending on whether the corresponding cell in column A is a number or not.

Using ISNUMBER With Conditional Formatting

One of the most powerful ways to use ISNUMBER is with conditional formatting. Conditional formatting allows you to automatically apply formatting (such as font color, cell color, or borders) to cells based on their values.

For example, let's say you have a list of sales figures and you want to highlight any values that are below a certain threshold. Here's how you could do it using ISNUMBER and conditional formatting:

  1. First, select the range of cells that you want to apply the formatting to.
  2. Next, click on "Format" in the top menu and select "Conditional formatting" from the drop-down menu.
  3. In the "Format cells if" drop-down menu, select "Less than".
  4. In the value field, type the threshold value.
  5. In the "Format cells if" drop-down menu, select "Custom formula is".
  6. In the formula field, type "=ISNUMBER(A1)" (replace A1 with the first cell in your selected range).
  7. Finally, choose the formatting options you want to apply.

That's it! Now any cell in your selected range that contains a value below the threshold will be automatically highlighted.

Why You Should Use ISNUMBER

If you work with spreadsheets on a regular basis, you know how frustrating it can be to have to manually check whether each cell contains a number or not. ISNUMBER takes care of that for you, making your life easier and saving you time.

Additionally, using ISNUMBER with conditional formatting allows you to quickly identify trends and outliers in your data.


In conclusion, ISNUMBER is one of the most useful formulas in Google Sheets. It allows you to easily check whether a value is a number or not, and can be used with conditional formatting to automatically highlight cells based on their values. So the next time you're working with numbers in Sheets, don't forget to use ISNUMBER!

Thanks for reading!

By clicking “Accept”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts. View our Privacy Policy for more information.