# Is Null

With the *Is Null* action node, you can verify whether a variable exists (i.e., is it a real value or a NULL value) and define what action follows - either route the customer to a new step in the workflow or trigger a new workflow.

For example, you can verify whether an expected response parameter from an API is available in the response received. 

{% hint style="success" %}
This node is typically used after an [*API Integration*](/flow/action-nodes/action-nodes-api-integration.md) node to check whether a variable exists within the returned payload.
{% endhint %}

<figure><img src="/files/9RrQ2C8v5j9TeDStSQzX" alt="" width="563"><figcaption><p>Setup an Is Null node</p></figcaption></figure>

![Example flow containing Is Null node](/files/-MeipKLWkpTGbWHXepuA)


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