Office of Recovery Services Child Support Calculator. The following worksheets are intended only as a guideline for estimating child support.Child support is calculated using the gross monthly income of both parents and the number of overnights the child spends in each household. To calculate the amount of support under Utah's current child support guidelines, you can use the official Utah Child Support Calculator. Enter each parent's gross monthly income. You can calculate your possible child support payment amount two ways: online, using our Child Support Calculator, or on paper, using worksheets. The following calculator provides an estimate of a potential alimony award in the State of Utah. See how parenting time affects the total. Red Law Utah helps you determine the amount of child support you will have to pay in Utah. Contact us today for help with your case!