Use hidden fields and URL parameters
Pass URL parameters (hidden fields) to your embedded Fillout forms to personalize text, track UTM campaigns, or track unique submissions for different respondents.
Overview
Passing data to your embedded Fillout form can be used to:
- Personalize text on your form via answer piping
- Track UTM campaigns
- Much more!
Pass dynamic URL parameters (hidden fields) to your embed
1. Register URL parameters, if you haven’t yet.
Add your parameter in the Settings page of your form. More information here.
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2. Paste the code
Select one of the Embed options followed by
Get the code
. Then paste into your site.
You can optionally customize how the embed and button will look.
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3. In the Embed code, add data attributes for each URL parameter
To pass a URL parameter to the embed, add a
data-[parameter]
attribute to the element in the snippet.For example, if you’re embedding this form on your site which is a Facebook-related campaign, and you have a URL parameter of
ref
, you can use data-ref="Facebook"
. Your embedding code will look something like this:<div data-fillout-id="cwb3NdqFmJus" data-fillout-embed-type="standard" style="width:100%;height:500px;" data-fillout-inherit-parameters data-fillout-dynamic-resize data-ref="Facebook"></div><script src="https://server.fillout.com/embed/v1/"></script>
Note: Embeds will automatically inherit URL parameters from the parent page that they’re on, so if your main site already has these, you simply need to register the parameter in your form to use it.
4. Share your form link
Once everything is set, click
Publish
in the upper right corner and share your form.