Child Support Calculator

What Is the Child Support Calculator?

The Child Support Calculator estimates a monthly child support obligation using the income-shares model used by most U.S. states. Both parents’ monthly net incomes are combined, a support percentage is applied based on the number of children, and each parent’s share of the obligation is proportional to their share of the combined income. The parent who does not have primary custody generally pays their share to the other parent. You can choose a Generic income-shares schedule, or the Illinois or Indiana schedules.

How to Use the Child Support Calculator

1. Enter Parent 1’s monthly net income and Parent 2’s monthly net income (take-home pay, in dollars).
2. Enter the Number of children.
3. Enter Custody with Parent 1 in overnights per year (0–365).
4. Choose the State schedule: Generic income-shares, Illinois, Indiana, or Other (uses the generic schedule).
5. Click Process.
6. Read the result: combined income, each parent’s income share, the support percentage applied, the basic obligation, each parent’s share, and the adjusted monthly amount. Use Copy or Download to keep it.

Worked Example

Parent 1 earns $6,000/month, Parent 2 earns $3,000/month, with 2 children, on the Generic schedule:

• Combined monthly income: $6,000 + $3,000 = $9,000
• Parent 1 share: 66.7%. Parent 2 share: 33.3%.
• Support percentage for 2 children: 27%
• Basic child support obligation: $9,000 x 27% = $2,430/month
• Parent 2 share: $2,430 x 33.3% = $810/month

Result: Parent 2 pays Parent 1 $810/month.

Limitations

• Known issue: the custody (overnights) input currently does not change the result. We tested 0 and 365 overnights with Parent 1 with the same incomes, and both returned the identical $810/month with the “adjusted (after parenting time)” figure equal to the unadjusted share. Treat the overnights field as informational until this is fixed, and do not rely on the tool for shared-custody adjustments.
• The schedules are simplified percentages, not your state’s official published support tables. Real guidelines include income brackets, self-support reserves, and other rules this tool does not model.
• The estimate does not include health insurance premiums, childcare costs, extraordinary medical expenses, prior support orders, or arrears.
• The result is a planning estimate only. It is not legal advice, not a court order, and not a substitute for your state’s official child support calculator or a family-law professional.

Frequently Asked Questions

How does the income-shares model work?

Both parents’ net incomes are added together, a percentage based on the number of children is applied to the combined income to get the basic obligation, and each parent owes a share proportional to their income. The non-custodial parent typically pays their share to the custodial parent.

Does changing the overnights change the payment?

It should, but in the current version it does not — this is a known issue. Both 0 and 365 overnights with Parent 1 produced the same $810/month in our test. Use the tool for the basic income-shares figure only, and check parenting-time adjustments against your state’s official calculator.

Which states does the calculator cover?

It offers a Generic income-shares schedule plus Illinois and Indiana options, and an Other option that uses the generic schedule. Even for Illinois and Indiana, the figures are simplified estimates, not the official state calculations.

Can I use this result in court?

No. Courts apply their state’s official guidelines and consider factors this tool ignores, such as insurance, childcare, and parenting time. Bring the official state calculator output and supporting documents to any hearing.