WP Referral Code is a WordPress plugin that helps you generate a unique referral code for each of your users, enabling you to start your own version of referral marketing. Upon user registration, the plugin captures the refer code automatically. Additionally, WP Referral Code provides a user-friendly "copy refer link box" that allows users to easily copy and share their referral link.
This plugin is dependent only on the WordPress core and can be used with all other plugins. However, the logic after successful referral registration is up to you. To help with this, two important hooks are provided. For more information on how to use them, please refer to the plugin documentation, which can be found on the plugin website
Documentation.
Several shortcodes are available to help you place things where they need to be. A list of these shortcodes can be found in the plugin options.
All information related to the referral status of a user can be found on the user edit page (Dashboard->Users->select a user). Here, you can view how many users the user has invited and who they were referred by.
note: on activation plugin will create refer codes for all of your users.