Populate dropdown options with a webhook

Fillout supports dropdowns with dynamically populated options, populated from a REST API endpoint of your choice.

Coming Soon: This feature is not yet generally available in Fillout but is coming soon. Stayed tuned for updates here and on LinkedIn.

What is a webhook

A webhook is a way for one system (like Fillout) to send real-time data to another system (like the 3rd party tools you use) as soon as an event occurs. Under the hood, a webhook is an HTTP callback and can be a GET, PUT, POST or DELETE request.

How to use the webhook integration

1. Add a Webhook

Go to the Integrations tab and click Webhook.
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2. Add a Pre-fetch step to the Webhook integration

Toggle the Advanced view switch, then scroll down to Pre-fetch. Click + Add new, then choose a recognizable name for your pre-fetch (the name is used only for your reference).
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You can learn more about pre-fetch steps here.

3. Setup your Pre-fetch step

Enter the base URL of your API and any parameters you would like to pass.
Your API endpoint must return an array of objects, with each object containing a "value" property. For example:
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4. Choose a dropdown field to pre-populate

If your API endpoint successfully returns an array of object as described above, you'll see an option to choose a dropdown to pre-populate. You can choose from any existing dropdown in your form.
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That's it! Your dropdown will now populate its options from your Webhook.

Related article

Send form submissions to a webhook