how to get previous step values in next step in drupal multi step form?
There are so many ways to send data from one from to other.


You can use session
You can also pass value in url


Example of pass by value

function register_form_submit($form, &amp;$form_state){
$name = $form_state['values']['name'];
$age = $form_state['values']['age'];

$data = array(
    'query' =&gt; array(
         'name' =&gt; $name,
         'age' =&gt; $age,
        )
    );

$form_state['redirect'] = array('/success', $data);
}


here is a link you can refer for send data

https://www.drupal.org/node/2064545