> For the complete documentation index, see [llms.txt](https://help.novacuraflow.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.novacuraflow.com/development/flowscript/functions/text-functions/isnull.md).

# IsNull

This Flow Script tutorial explains how to use the IsNull function with syntax and examples.

### **Description**‌

The IsNull function replaces empty input values with the specified replacement value. If the input value is not empty will the value not be replaced.

### **Syntax**

‌The syntax for the IsNull function is:

`IsNull(input, replacement)`

#### ‌**Parameters**

input - the string which, if it is empty, will be replaced. 

replacement - the value which will replace an empty input.

### **Returns**

‌The IsNull function returns a string. 

### **Example**‌

Let's look at some IsNull function examples and explore how to use the IsNull function.‌

```
IsNull("", 0)
Result: 0
```


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