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Family

Child Support Calculator

Estimate monthly child support payments based on both parents' incomes, custody percentage, and additional child-related expenses using the income shares model.

Updated July 2026 · Editorial standards

Estimated monthly child support
$975/mo
Basic support obligation
$2,000
Combined monthly income
$8,000
Who paysParent 2 pays Parent 1Parent 1 share$1,625Parent 2 share$975

Parental Information

$
$
children
%

Key figures

Est. monthly payment
$975
Basic support obligation
$2,000
Parent 1 share
$1,625
Parent 2 share
$975

Parent 2 pays Parent 1 an estimated $975/month. Combined income: $8,000/mo — Parent 1 earns 62.5% of total and Parent 2 earns 37.5%.Basic obligation for 2 children: $2,000/mo plus $600/mo in childcare and insurance = $2,600/mo total obligation.

Est. monthly support
$975/mo
By KalkWiseVerified against official sources Updated July 2026

What is the child support calculator?

In short

With Parent 1 earning $5,000/mo and Parent 2 earning $3,000/mo, the combined obligation for 2 children is $2,000/mo plus $600 in childcare/insurance. Parent 2 owes $975/month to Parent 1 (the primary custodian). Obligations scale with income — a parent earning twice as much pays twice as much.

This calculator uses the income shares model — the most common US child support guideline — to estimate monthly support payments. It combines both parents' incomes, applies a per-child percentage, and adds childcare and health insurance costs, then splits the total by each parent's income share. The custodial parent (higher custody %) receives payments from the non-custodial parent.

How to use this calculator

  1. 1Enter both parents' gross monthly income (before taxes)
  2. 2Set the number of children and custody percentage for Parent 1
  3. 3Add monthly childcare and health insurance costs
  4. 4Read the estimated monthly payment and which parent pays

The formula

obligation=C×p%+childcare+insurance
payment=obligation×s₂%
Basic obligation = combined income × per-child percentage (17% for 1 child, 25% for 2, 29% for 3, up to 33% for 5+). Add childcare and health insurance costs. Each parent's share equals their % of combined income. The non-custodial parent pays their share to the custodial parent.
C
— Combined monthly gross income
p%
— Per-child percentage from income shares table
s₁
— Parent 1's share of combined income

Worked example

The scenario

Parent 1 earns $5,000/mo, Parent 2 earns $3,000/mo, 2 children, Parent 1 has 70% custody, $400/mo childcare, $200/mo insurance.

gives

The result

Combined income: $8,000. Basic obligation (2 children): $8,000 × 25% = $2,000. Add $400 + $200 = $600. Total: $2,600. Parent 2's share: 37.5% × $2,600 = $975/month paid to Parent 1.

Common use cases

  • Budgeting before or during a divorce proceeding
  • Understanding what a court might order vs. a negotiated agreement
  • Modeling how a raise or income change affects support obligations
  • Planning finances as either the paying or receiving parent

Limitations & assumptions

  • Uses a simplified income shares percentage table — courts use official state-published obligation tables that vary by state
  • Does not model split custody, shared parenting adjustments, or parenting time credits
  • Does not account for extraordinary expenses (private school, medical needs, travel for visitation)
  • Legal advice from a family law attorney is required before relying on this for any court proceeding

Frequently asked questions

Using the income shares model, if combined income is $7,000/mo and you earn 57% of it, and the basic obligation for 2 children is $1,750/mo, your share is about $998/month. Actual amounts depend on your state's guidelines and any deductions the court allows.

Disclaimer: KalkWise calculators are provided for general informational and educational purposes only and do not constitute financial, investment, tax, or legal advice. Results are estimates based on the figures you enter and the assumptions described above. Actual outcomes will vary. Consult a qualified professional before making financial decisions.