# ISNUMBER

The **ISNUMBER** function returns *TRUE* if the specified value is a valid number. It returns *FALSE* if the value is not numeric. It is commonly used with *IF* and other conditional functions to validate numeric inputs before performing calculations.

### Syntax

```javascript
ISNUMBER(value)
```

### Arguments

* value - The value to evaluate.

### Return value

Returns *TRUE* if the value is a numeric value; otherwise, returns *FALSE*.

### **Example**

<pre class="language-javascript"><code class="lang-javascript"><strong>IF(ISNUMBER(2026 Actuals), 2026 Actuals*1.05, "Not a number")
</strong></code></pre>

In this example, the **ISNUMBER** function checks whether *2026 Actuals* contains a numeric value. If the condition is *TRUE*, the formula applies a 5% increase to the value; otherwise, it returns '*Not a number'*.

<figure><img src="/files/ZZx5VH2xTwxOsQwhrfqz" alt=""><figcaption></figcaption></figure>

### **Excel equivalent**

[ISNUMBER](https://support.microsoft.com/en-us/office/is-functions-0f2d7971-6019-40a0-a171-f2d869135665)


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