Family Law
Child Support Calculator
Estimate monthly child support payments using the Income Shares Model, the standard formula used in most US states.
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April 2026
Child Support Calculator
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The Income Shares Model Explained
Most states use the "Income Shares Model" to calculate child support. The philosophy is that a child should receive the same proportion of parental income they would have received if the parents lived together.
- Combine Income: Parent A's income + Parent B's income = Total Combined Income
- Determine Basic Support: Use a state-provided economic table to figure out the basic child support obligation based on the combined income and number of children.
- Proportional Share: Divide the basic support obligation between the parents based on their share of the combined income. (e.g., if Parent A earns 60% of the total income, they are responsible for 60% of the obligation).
- Add-ons: Add health insurance, childcare, and extraordinary expenses, distributed proportionally.
- Parenting Time Adjustment: Adjust the paying parent's obligation downwards if they host the child for a substantial number of overnights.
Important Legal Disclaimer
This calculator provides a generalized estimate. State-specific tables vary widely. Courts may also deviate from guidelines if strict application is unjust. Consult a family attorney or your state's child support agency for accurate numbers.
Frequently Asked Questions
The Income Shares Model (used in about 40 states) estimates the total amount parents would spend on a child if they lived together. The obligation is divided between the parents proportionally based on their respective incomes.
Yes. If parents have roughly equal parenting time (shared physical custody), the higher-earning parent usually pays less support than if the other parent had sole custody, because both parents are directly covering the child's expenses during their time.
Extraordinary costs like health insurance premiums for the child, out-of-pocket medical expenses, and work-related childcare are typically added to the basic support obligation and divided proportionally between the parents.
This calculator uses a generalized Income Shares Model. While the underlying math is similar across most states, each state publishes its own specific economic tables and has unique rules for taxes, mandatory deductions, and caps. For an exact court-admissible figure, consult a local family law attorney.