How to Use the ISNUMBER Function in Excel (Check If a Cell Is a Number) The ISNUMBER function checks whether a cell contains a number and returns TRUE or FALSE. It’s very useful for data validation and cleaning tasks. 🧩 Syntax: =ISNUMBER(value) 📌 Parameters: value: The cell or expression you want to test 💡 Example: =ISNUMBER(A1) If A1 contains 123 , it returns: TRUE If A1 contains "Hello" , it returns: FALSE 🔁 Use Cases: Testing whether a formula returns a number Combining with IF to filter numeric values Validating numeric inputs in forms Working with functions like SEARCH or VALUE 🧠 Bonus Tip: Use with SEARCH or FIND to detect if text exists: =IF(ISNUMBER(SEARCH("apple", A1)), "Found", "Not Found") ISNUMBER simplifies logic-based formulas in your Excel workflows. For more Excel mastery, follow ScriptDataInsights.