Child Support Calculator by State

Three models, one goal

Federal law requires every state to have presumptive child support guidelines, but it leaves the formula to the states. Most use an income shares model: both parents' incomes are combined, a basic obligation is read from a schedule, and each parent pays a share proportional to income. Florida, Illinois, Pennsylvania, Virginia, Washington and New York work this way, though New York applies flat percentages rather than a schedule and Virginia uses gross rather than net income.

A smaller group, including Texas, Wisconsin and Nevada, uses a percentage-of-income model that considers only the paying parent's income. A few states use the Melson formula, which first reserves a self-support amount for each parent. Whatever the model, the guideline amount is presumed correct and a judge needs findings to deviate from it.

What changes from state to state

The inputs that matter most differ by state. Parenting time changes the result directly in California, Florida, Illinois, Pennsylvania, Virginia, Wisconsin and Nevada but has no automatic effect in New York, Texas or Washington. Income caps range from Texas's $11,700 of monthly net resources to New York's $193,000 of combined annual income, while Washington's table now runs to $50,000 a month. Add-ons for childcare and health insurance are split equally in California and by income share in most other states.

Each state page explains its own rules in plain language, shows a worked example, and links to the statute so you can check any number yourself.

How to use these estimates

Enter gross income if you want the calculator to estimate taxes, or net income if you already have a figure from a worksheet. Run a few scenarios, such as different parenting schedules, to see how sensitive the result is. Then take the line-by-line breakdown to a mediator or attorney, or into your state's official calculator, to confirm it against your actual tax situation.