Learn how to calculate child support in Arizona, including how to collect, enforce, and change your current support order. States generally use one of three models to determine the base child support amount due.Explanations of each model and the states that use them follow. The size of your child support payment depends heavily on where you live. The Child Support Calculator is an interactive program that will calculate a child support amount based on the Arizona Child Support Guidelines. DISCLAIMER Calculator: The Arizona Administrative Office of the Courts provides this online tool you can use to calculate a child support estimate. If you work or reside in a state where a state income tax is assessed against your income, enter the monthly amount. If child support income is attributed to the parent receiving support, appropriate childcare expenses may also be attributed. Every state has its own guidelines for determining how much child support parents should pay. Arizona uses a formula to determine which parent pays support and how much.