Using Gravity Forms ‘gform_pre_submission’ PHP action

The gform_pre_submission Gravity Forms action hook allows you to modify the submitted form values after validation, but before the entry is stored and notifications are sent.


Apply to all forms:

add_action('gform_pre_submission', 'pre_submission');

Apply to a specific form (e.g., form ID 5):

add_action('gform_pre_submission_5', 'pre_submission');


  • $form (Form Object): The current form.

More information

See Gravity Forms Docs: gform_pre_submission

The action hook is located in GFFormDisplay::process_form() in form_display.php.


Populate a field

This example sets a new value for field 14:

add_action('gform_pre_submission', 'pre_submission_handler');
function pre_submission_handler($form) {
    $_POST['input_14'] = 'new value for field 14';

Populate a field using the value from another field

This example sets the value of field 14 to the value of field 5 for form ID 1:

add_action('gform_pre_submission_1', 'pre_submission_handler');
function pre_submission_handler($form) {
    $_POST['input_14'] = rgpost('input_5');

Populate a field with the age

This example calculates the age based on the date field value and populates field 11 with the age for form ID 5:

add_action('gform_pre_submission_5', function($form) {
    $date_field_id = '10';
    $date_field = GFAPI::get_field($form, $date_field_id);

    $value = $date_field->get_value_submission(array());
    $date_value = GFFormsModel::prepare_date($date_field->dateFormat, $value);

    $today = new DateTime();
    $diff = $today->diff(new DateTime($date_value));

    $_POST['input_11'] = $diff->y;