Set a custom Field Group key for any Field Group. In order to change the key, you’ll have to display the “Slug” metabox. The field group key must begin with group_.

Note that PHP & Json export files will get updated accordingly.

Slug

#Retrieve Group Key

Group key is saved in the Field Group array, under the native key key. It can be retrieved using acf_get_field_group(). Usage example:

$field_group = acf_get_field_group('group_my_field_group');

/**
 * array(
 *     'key'    => 'group_my_field_group',
 *     'title'  => 'My Field Group',
 *     'active' => true,
 * )
 */