Include form fields as redirect URL parameters on an embedded form

Developer Support APIs & Integrations
2

You could achieve this by using the onFormSubmit callback and switching the form to use an inline message instead of a redirect (explained below).

hbspt.forms.create({
 portalId: 'xxxxxxxx',
 formId: 'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx',
 inlineMessage: 'Your submit message here',
 onFormSubmit: function($form){
 setTimeout( function() {
 var formData = $form.serialize();
 window.location = "http://www.yoururl.com?" + formData;
 }, 250 ); // Redirects to url with query string data from form fields after 250 milliseconds.
 }
});

Because you have access to the jQuery $form object inside the onFormSubmit listener you can serialize the forms data and append it to a url to redirect to after the form is submitted. This only works if you have the inlineMessage set and disable the redirectUrl for the form.

See if that helps you out.