This page will help you calculate the figures a New York judge would consider in determining how much should be paid in maintenance and child support. Worksheets to calculate guideline amounts of maintenance and child support.Optional tools to help with calculations are below. The amount you get depends on what the father's income is, what your income is, how many children you have together, and what your children's basic needs are. The amount of child support that either parent may have to pay following a divorce is based on several factors, and one of those factors is alimony. If you are going through a divorce in New York, one question you may be asking is how to calculate alimony. When calculating New Jersey child support, courts consider both parents' income. This combined income is then used to determine the amount of support. 1. Fill out a child support modification petition. 2. File the petition with the Family Court that most recently established your order. 3.