# Metering and Charging

> Metering and charging model for Document Understanding APIs in Automation Suite, based on AI Units consumption for classification and extraction by project type.

Charging is based on AI Units and it takes into account the classification and extraction models consumption. Depending on the project type, visit the following pages:

* [AI Center-based projects](https://docs.uipath.com/document-understanding/automation-suite/2024.10/classic-user-guide/metering-charging-logic)
* [Modern projects](https://docs.uipath.com/document-understanding/automation-suite/2024.10/user-guide/metering-charging-logic)