You can get EPP code at HostGator by contacting them or following these steps:
- Login to your HostGator customer portal.
- Go to the Domains menu.
- Select the relevant domain name.
- Navigate to the icons on the left and click on the Domain Locking option.
- On the newly opened page, toggle the button to the Locking OFF position to unlock the domain and click Save Domain Locking to save the changes.
- Click the Request Your EPP Key button to obtain your Auth code.
Completing these actions you will receive an email with your domain authorization code in just a few minutes. Now you will be able to transfer your domain to Hostinger :)
NOTE: You can also check this article for more information about the EPP code.