Child Support Calculator
Estimate your monthly child support obligation or entitlement based on your state's official guidelines. Covers all 50 states with income shares, percentage of income, and Melson formula models.
How Child Support Is Calculated
Child support in the United States is determined using one of three primary models, each reflecting a different philosophy about parental financial responsibility. Understanding which model your state uses is the first step toward estimating your obligation or entitlement.
Income Shares Model
The income shares model is the most widely used approach, adopted by approximately 41 states and the District of Columbia. Under this model, courts combine both parents' gross or net incomes to determine the total amount that would have been spent on the children if the family were still intact. Each parent then pays their proportional share of that total obligation based on their percentage of the combined income. For example, if one parent earns 60% of the combined income, they would be responsible for 60% of the child support obligation. This model acknowledges that children should receive the same proportion of parental income they would have received if the parents lived together.
Percentage of Income Model
About six states—including Texas, Wisconsin, Mississippi, Nevada, Alaska, and North Dakota—use the percentage of income model. This simpler approach applies a flat percentage of the noncustodial parent's income based solely on the number of children. The custodial parent's income is generally not considered in the basic calculation. Percentages typically range from about 17% for one child to 40% or more for five or six children, though exact figures vary by state. Some states apply the percentage to gross income, while others use net income.
Melson Formula
Delaware and a small number of other jurisdictions use the Melson formula, which is a more nuanced variation of the income shares approach. The Melson formula involves three steps: first, it ensures each parent retains enough income to meet their own basic needs (the self-support reserve); second, it calculates each parent's share of the children's primary needs; and third, it applies a "standard of living adjustment" (SOLA) that allocates a percentage of any remaining income to provide children with a higher standard of living. This model is considered the most thorough in protecting both parents' and children's financial interests.
Understanding Your State's Formula
When you select a state in the calculator above, the tool automatically applies that state's specific calculation model. Each state has its own guidelines schedule, income thresholds, and adjustment rules. Here is what changes based on your state selection:
- Base percentages — The percentage of combined or individual income used to determine the basic obligation varies by state and by the number of children.
- Income caps — Some states cap the income considered in the calculation. For instance, New York caps combined parental income at $163,000 per year (as of 2024), while Texas caps net resources at $184,620.
- Self-support reserves — Most states ensure the paying parent retains enough income to cover basic living expenses. This reserve typically ranges from $950 to $1,350 per month.
- Shared custody thresholds — States differ on when shared parenting time triggers an adjustment. Some states begin adjusting at 20% of overnights, while others require 35% or more.
- Low-income adjustments — Several states reduce obligations for parents earning below a certain threshold to prevent undue hardship.
Because of these variations, the same family situation can produce significantly different child support amounts depending on the state. This calculator incorporates state-specific data to provide the most accurate estimate possible without replacing a formal court calculation.
Factors That Affect Child Support
While income is the most significant factor in determining child support, courts consider a range of additional circumstances that can increase or decrease the final amount. Understanding these factors helps you prepare for what a court might order.
Parental Income
Both parents' incomes are central to the calculation. Income typically includes wages, salaries, bonuses, commissions, self-employment earnings, rental income, investment returns, and some government benefits. Courts may also impute income to a voluntarily unemployed or underemployed parent—meaning they may assign an earning capacity based on education, work history, and local job market conditions.
Parenting Time (Overnights)
The number of overnights each parent spends with the children directly affects the support amount. In most income shares states, when the noncustodial parent has the children for a significant number of overnights (often above 25-35% of the year), a shared custody adjustment reduces the support obligation. This reflects the increased direct spending that occurs during those overnights. Moving from 100 overnights to 182 overnights per year (equal custody) can substantially change the calculated amount.
Healthcare Costs
The cost of providing health insurance for the children is factored into most state calculations. This includes monthly premiums for coverage, as well as recurring out-of-pocket expenses like copays, prescriptions, and other uninsured medical costs. Courts typically divide these costs proportionally between parents based on their income shares.
Childcare Expenses
Work-related childcare costs—including daycare, before- and after-school programs, and summer care—are added to the basic obligation in most states. These costs are then divided between parents in proportion to their income shares. Childcare expenses can add hundreds of dollars per month to the total obligation.
Special Circumstances
Courts may deviate from the standard guidelines when special circumstances exist. These can include a child's special needs or disabilities, extraordinary educational expenses, travel costs for long-distance visitation, and significant disparities in the parents' standards of living. Existing support obligations for children from other relationships may also reduce the amount available for the current calculation.
How to Use This Calculator
This child support calculator is designed to give you a reliable estimate based on your state's guidelines. Follow these steps for the most accurate result:
- Select your state — Choose the state where the child support order will be filed. The calculator will automatically apply that state's formula and rules.
- Enter both parents' gross monthly incomes — Use gross (pre-tax) income including wages, salaries, bonuses, and other earnings. Be as accurate as possible for a reliable estimate.
- Set the number of children — Click the number of children covered by this support order. Only include children of both parents, not stepchildren or children from other relationships.
- Adjust your overnights — Use the slider to set the approximate number of overnights per year you have (or expect to have) with the children. This significantly affects the calculation in most states.
- Add additional costs — Click "More options" to enter healthcare premiums, childcare costs, and other child-related expenses. Including these provides a more complete picture.
- Review your results — The calculator instantly shows your estimated monthly and annual obligation, a breakdown of the calculation, and which parent pays whom.
- Compare scenarios — Use the "Compare Scenarios" tab to see how changes in income or custody time affect the support amount. This is useful when negotiating parenting plans.
Frequently Asked Questions
How accurate is this calculator?
This calculator provides estimates based on each state's published guidelines, percentage schedules, and adjustment rules. It uses the same general formulas that courts apply, but actual court-ordered amounts may differ due to judicial discretion, local rules, detailed income verification, and case-specific factors that a simplified calculator cannot fully capture. Use this as a starting point for understanding your potential obligation, and consult a family law attorney for a precise determination.
What income is included in child support calculations?
Most states define income broadly for child support purposes. It typically includes: wages and salaries, overtime pay, bonuses and commissions, self-employment income, rental and investment income, pension and retirement distributions, Social Security benefits (in many states), workers' compensation, unemployment benefits, and alimony received from other relationships. Some states exclude certain types of income like public assistance (TANF, SSI) or income from a new spouse. Always check your state's specific definition of "gross income" for child support purposes.
How does custody time affect child support?
Custody time—measured in overnights per year—is a significant factor in most state calculations. When the noncustodial parent has more overnight time with the children, they are directly spending more on housing, food, and day-to-day needs. Most states reduce the child support obligation when overnights exceed a certain threshold (commonly 25-35% of the year, or roughly 91-128 nights). The more overnights you have, the lower the support payment is likely to be, though it rarely reaches zero even in equal (50/50) custody situations because courts also consider income disparity.
Can child support be modified?
Yes, child support orders can be modified when there is a substantial change in circumstances. Common grounds for modification include: a significant increase or decrease in either parent's income (typically 15-25% or more), a change in the custody or parenting time arrangement, a change in the children's needs (such as developing special needs), loss of employment (involuntary), a change in healthcare or childcare costs, or remarriage or new children (in some states). To modify support, you typically file a motion with the court that issued the original order. Many states also conduct periodic reviews every few years.
What if a parent is unemployed?
If a parent is involuntarily unemployed, courts may temporarily reduce the child support obligation based on the parent's actual income (which may be zero or limited to unemployment benefits). However, if a court determines that a parent is voluntarily unemployed or underemployed—meaning they are capable of earning more but choose not to—the court may "impute" income. Imputed income is based on the parent's education, work history, skills, and the prevailing wages in their area. This prevents a parent from avoiding child support by deliberately reducing their earnings.
How long does child support last?
In most states, child support continues until the child turns 18. However, there are important exceptions. Many states extend support until the child graduates from high school if they turn 18 before graduating (often capped at age 19 or 20). Some states, like New York, may require support until age 21. If a child is disabled, support may continue indefinitely. College expenses are not automatically included in child support in most states, but some states (like New Jersey, Indiana, and others) allow courts to order parents to contribute to higher education costs. Each state has its own rules, so check your local laws.
Are child support payments tax deductible?
No. Under current federal tax law (since the Tax Cuts and Jobs Act of 2017), child support payments are neither tax-deductible for the paying parent nor taxable income for the receiving parent. This is different from alimony, which had its tax treatment changed for agreements executed after December 31, 2018. Child support is considered a parental obligation rather than income, so it has no direct tax consequences for either party. However, who claims the child as a dependent (for the child tax credit and other benefits) is a separate issue that parents and courts often negotiate.
What counts as income for child support?
Income for child support is defined more broadly than just a W-2 paycheck. Courts consider all sources of income including: regular employment wages, self-employment profits, freelance and gig economy earnings, rental property income, stock dividends and capital gains, trust distributions, military pay and allowances, disability benefits (in most states), workers' compensation, and even regular monetary gifts. Some states also consider the earning potential of significant assets. Most states allow certain deductions from gross income, such as taxes actually paid, mandatory retirement contributions, union dues, and existing child support obligations for other children.
How do I file for child support?
You can file for child support through your local family court or your state's child support enforcement agency (often part of the Department of Social Services or a similar agency). The process generally involves: filing a petition or application with the court, establishing parentage if the parents were never married (through acknowledgment or DNA testing), providing financial disclosure documents (pay stubs, tax returns, expense records), attending a court hearing or mediation where the judge applies the state guidelines, and receiving a court order that specifies the monthly amount, payment method, and healthcare provisions. Many states allow you to begin the process online. You can also seek child support as part of a divorce proceeding.
What happens if child support isn't paid?
Failure to pay court-ordered child support carries serious consequences. Enforcement tools available to courts and child support agencies include: wage garnishment (automatic deduction from the obligor's paycheck), intercepting federal and state tax refunds, suspending driver's licenses and professional licenses, reporting to credit bureaus (which damages credit scores), seizing bank accounts and other assets, placing liens on property, denying or revoking passports, and in severe cases, contempt of court proceedings that can result in fines or jail time. Most states also charge interest on unpaid child support arrears. If you are unable to pay due to a change in circumstances, it is critical to file for a modification promptly rather than simply stopping payments.
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