Office of Recovery Services Child Support Calculator. The following worksheets are intended only as a guideline for estimating child support.You can calculate your possible child support payment amount two ways: online, using our Child Support Calculator, or on paper, using worksheets. See how parenting time affects the total. Child support is calculated using the gross monthly income of both parents and the number of overnights the child spends in each household. The following Utah child support obligation calculators can give you some guidance on "how much I have to pay for child support". You may use this worksheet and instructions to MANUALLY CALCULATE the child support obligation using the table found in Utah Code 81-6-304. All of these calculators take into account income, parent time, and how many children you have in your custody. This calculator is intended only as a guideline so parents can estimate how much child support they will need to pay or receive from the other parent. Alimony calculations will vary from state to state and from judge to judge.