Display user registration date

I want to show user registration date like

Member since: 15,dec 2012.

I have a code

<?php echo date("M Y", strtotime(get_userdata(get_current_user_id( ))->user_registered)); ?>

but it show same date in all users profiles. Can some one please tell me how I fix that.

get_current_user_id() give you the user id of the logged in user. And that is: you.

You have to get all users:

<?php
        $users = get_users();

        foreach( $users as $user ) {

            $udata = get_userdata( $user->ID );

            $registered = $udata->user_registered;

            printf( '%s member since %s<br>', $udata->data->display_name, date( "M Y", strtotime( $registered ) ) );
        }