Worksheets to calculate guideline amounts of maintenance and child support. Optional tools to help with calculations are below.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. The New York government website offers an online calculator that can help you determine how much child support you will be responsible for. New York uses a specific percentage calculation for child support. It takes the incomes of both parents into account. If you are going through a divorce in New York, one question you may be asking is how to calculate alimony. One of the first steps in the child support process is identifying the child's parents. The formula uses the parties' incomes and salary, as well as whether or not child support is being paid to perform a calculation. 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.