> For the complete documentation index, see [llms.txt](https://developers.getgeoflow.com/geoflow-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers.getgeoflow.com/geoflow-docs/feature/form/autofill-form-field.md).

# Autofill Form Fields

### How Does It Work?

Apply the Geo Input data attribute to a \<input> or \<textarea> element, using a value corresponding to a visitor data property to autofill that field.

### How To Implement

<table><thead><tr><th>Attribute Name</th><th width="268.3333333333333">Attribute Value</th><th>Which Page Element?</th></tr></thead><tbody><tr><td>data-geo-input</td><td>propertyName</td><td>&#x3C;input> or &#x3C;textarea></td></tr></tbody></table>

Only one property name is supported in the value. The property name is case-sensitive and must match the 'Property Variable' noted in the [Visitor Data Properties table](/geoflow-docs/overview/visitor-data-properties.md).

If the \<input> field is a checkbox or radio and if the visitor data property returns a boolean (true or false), then the \<input> field will be checked/unchecked accordingly.

The Geo Form data attribute does not need to be added to the \<form> element for the Geo Input data attribute to function.

### Examples

```html
<!-- This Text Field Will Be Prefilled with the Visitor's Country Name-->
<input type="text" data-geo-input="countryName">

<!-- This Checkbox Will Be Checked If the Visitor Is From the EU -->
<input type="checkbox" data-geo-input="isEU">

<!-- This URL Field Will Be Prefilled with the Visitor's Referer -->
<input type="url" data-geo-input="referer">
```


---

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