Credits in Hexomatic are basically for running the automation. Among the two credit types, the regular (auto-renewal) credits are spent when you apply the built-in automation, i.e., 1 credit per built-in automation. On the other hand, the premium (third-party supported) automation requires premium credits in addition to the regular credits. The premium credit expenditure varies for each service. Example: text-to-speech automation costs 0.0008 premium credits per character conversion plus 1 regular credit.