How to Create and Add a Hidden Field to Your Form

A hidden field lets you collect information without asking attendees to enter it themselves. In the registration editor, you create a hidden field by adding a question with the Scripted type. Scripted fields do not appear as visible questions on the registration form.

Step-by-Step Configuration Instructions

Step 1: Open the registration settings

Open your webinar.
Navigate to Customize Your Webinar > Registration.
Open the Registration page questions.

This section contains the standard registration details and any additional questions added to the form.

Step 2: Add a Scripted question

Click Add Question.
Open the Type dropdown.
Select Scripted.

The Scripted type creates a hidden field instead of a question that attendees can see.

Step 3: Add the field details

Complete the fields shown in the add-question form:

In Default value, enter an optional fallback value.

The default value is used when the hidden field does not receive a value from your page script.
In Name, enter a unique name for the field.

For example:

lead_source

Use a simple name without spaces. Avoid using a name that is already assigned to another custom question or a built-in registration field.
Leave Required turned off unless you have a specific reason to use it. Since the field is hidden, attendees cannot fill it in themselves.
Click Submit.

If you decide not to add the field, click Cancel instead. The field name must be entered before Submit becomes available, and duplicate names among existing custom questions are not allowed.

The new field appears in the Added Questions list and is marked Scripted.

Step 4: Save your changes

Click Save & Continue in the wizard footer.
Wait for the confirmation that your registration settings have been saved.

If you are not ready to save the webinar permanently, you can select Save to draft instead.

Before you begin:

Open the webinar you want to update.
Make sure the webinar uses a registration page. The Registration page questions section is not shown for Public Webinar pages.
Choose a name for the field, such as lead_source or campaign_id .
If a page script will fill the field, make sure the script can use the exact field name you enter.

How to Check Your Setup

Use the following checks to confirm that the hidden field is working:

Open the registration page preview.
Confirm that the new field is not visible to attendees.
Complete a test registration.
Check the system that receives the registration data and confirm that the custom field is present.
If you entered a Default value and are not using a page script, confirm that the fallback value was submitted.
If a page script is being used, confirm that it writes to the exact field name using this format:

customFields.field_name

Replace field_name with the value entered in the Name field. For example, if the field name is lead_source , the script should target customFields.lead_source .

Connected integrations may handle custom fields differently, so verify the field mapping separately in the receiving system.

Common Issues and Solutions

Symptom	Root Cause	Resolution
The field appears as a visible question on the registration page.	A visible question type, such as Text, was selected instead of Scripted.	Remove the question, click Add Question, select Scripted, enter the field details, click Submit, and save the Registration step.
The Submit button is disabled.	The Name field is blank or duplicates the name of another custom question.	Enter a nonblank, unique name. A blank Default value does not prevent the field from being submitted.
The field value is blank after registration.	The page script used the wrong field name, returned an empty value, or both the submitted value and Default value are empty.	Confirm that the script targets `customFields.<Name>` , make sure it provides a value, or add a fallback Default value.
The field is present in the registration data but missing from an integration.	The connected integration may not automatically map or display custom fields.	Check the integration’s custom-field mapping separately from the StealthSeminar registration settings.
The field disappears after leaving the editor.	The Registration step was changed but not saved.	Return to Customize Your Webinar > Registration and click Save & Continue or Save to draft.
The Registration page questions section is not visible.	The webinar is using a Public Webinar registration flow.	Use a registration page that collects attendee information. Public Webinar pages do not display this question section.