Child Support Estimator — All
50 States

Yes. You can estimate your own child support payments by entering the state where the order will be filed, each parent's income, the number of children, parenting time or overnight totals, health insurance premiums, work-related child care, and any existing support obligations. The calculator gives a planning estimate under state guidelines, but the court or child support agency makes the final order.

Child support calculations vary by state. The most common method is the Income Shares model (used in 41 states), which looks at both parents' combined income and allocates support proportionally. Six states use the Percentage-of-Income model, where support is a set percentage of the non-custodial parent's income. Three states (Delaware, Hawaii, Montana) use the Melson Formula, which adds a self-support reserve before calculating. This calculator applies your state's specific formula.

Yes. Child support can typically be modified when there's a substantial change in circumstances — such as a significant change in either parent's income, a change in custody time, or the child's needs changing. Most states define 'substantial' as a 15–25% change in the calculated amount. Either parent can petition the court for a modification. Support orders are not retroactive; modifications only apply going forward.

Yes, in most states. The more overnights the non-custodial parent has, the lower their child support obligation. Many states apply a custody adjustment when the non-custodial parent has the child at least 30–40% of the time (roughly 109–146 overnights per year). Reaching that threshold can significantly reduce monthly support amounts.

In most states, child support is paid until the child turns 18. Some states extend support to age 19 or until the child finishes high school, whichever comes first. A few states, including New York and Massachusetts, can order support through age 21 in certain circumstances. College expenses are handled separately — some states allow courts to order contribution to college costs, others do not.

Most states include all regular income sources: wages, salary, self-employment income, commissions, bonuses, rental income, dividends, and benefits like disability or unemployment. Courts can also impute income to a parent who is voluntarily unemployed or underemployed — assigning them the income they could reasonably earn based on their education and work history.