How is child support calculated if my income varies month to month?

Courts average your income over 12–24 months for irregular earners (freelancers, commission-based workers, gig economy dads, seasonal employees). Use the 'My income varies' toggle in this child support estimator to enter annual, quarterly, or monthly income — the tool computes your averaged monthly figure automatically, just like a family court would. Pro Tip: Gather your last 2 years of tax returns, 1099s, and bank statements. Courts want documented proof, not estimates. Statistic: Over 36% of American workers have some form of variable income — you're not alone

How is child support calculated in most states using the income shares model?

Most states use the 'Income Shares Model' which combines both parents' gross incomes, then calculates each parent's proportional share of the child's expenses. The non-custodial parent typically pays their share to the custodial parent. Key factors include number of children, overnight parenting time percentage, health insurance premiums, and daycare or childcare costs. Pro Tip: Always use GROSS income (before taxes) in calculations. Courts don't care what you take home—they care what you earn. Statistic: 47 out of 50 states use the Income Shares Model—only Texas, Wisconsin, and Mississippi use percentage-of-income formulas

Does more overnight parenting time reduce my child support obligation?

Yes, in most states. When you have more overnight parenting time (typically above 20-30% of overnights per year), courts apply a shared custody credit that reduces your monthly support obligation. At 50/50 custody, child support payments may be significantly reduced or eliminated if both parents earn similar incomes. Pro Tip: Track every overnight in writing. Verbal agreements don't count in court. Statistic: Dads with 35%+ parenting time see an average 40% reduction in support obligations

What income counts for child support calculations?

Gross income before taxes includes: salary, wages, bonuses, commissions, self-employment income, rental income, investment returns, Social Security, disability benefits, and sometimes imputed income if you're voluntarily unemployed or underemployed. Pro Tip: Keep 2-3 years of tax returns, pay stubs, and bank statements organized. You'll need them.

Can child support be modified after it's set — and how do I file?

Yes. You can request a child support modification when there's a 'substantial change in circumstances'—typically a 15-20% change in either parent's income, a change in the custody arrangement, or a significant change in the child's medical or educational needs. Most states allow modification petitions every 2-3 years. Pro Tip: File for modification the DAY your circumstances change—courts won't backdate. Statistic: 78% of modification requests based on job loss are granted when filed within 30 days of income change

How accurate is this child support calculator?

This calculator provides a reasonable estimate based on the Income Shares Model used by most states. Actual amounts may vary based on your state's specific guidelines, judge discretion, and factors not captured here. Always consult with a family law attorney for exact figures. Pro Tip: Use this estimate as a starting point for conversation with your lawyer—not as a guarantee.

What happens if I can't afford my child support payments after divorce?

Never stop paying—falling behind on child support can result in wage garnishment, driver's license suspension, passport denial, or even jail time. Instead, immediately file a motion to modify child support based on changed financial circumstances. Document your income change thoroughly and seek legal help if needed. Statistic: 97% of Fathers who proactively file for modification avoid wage garnishment

What if I lose my job — does child support automatically go down?

No, child support does NOT automatically adjust when you lose your job. You must file a motion for modification with the family court immediately. Until a judge approves the change, you're still legally responsible for the original monthly amount. Arrears (back child support) accumulate with interest and may not be forgiven even with documented job loss. Pro Tip: File within 14 days of job loss. Bring documentation: termination letter, unemployment claim filing, and active job search records. Statistic: Average time to child support modification approval: 45-90 days. Plan your budget accordingly.

What if we agree to 50/50 custody — will child support go to zero?

Not necessarily. Even with equal 50/50 parenting time, the higher-earning parent typically pays some child support to equalize the child's standard of living between households. The amount is usually smaller than standard custody arrangements, but zero support requires near-equal incomes and expenses. Pro Tip: Calculate both parents' adjusted income, not just the difference. Some states cap support reductions at 50/50. Statistic: At 50/50 custody with a $20K income difference, expect roughly $200-400/month in support to the lower earner

What if my ex quits her job or reduces hours intentionally?

Courts can 'impute' income to your ex based on her earning capacity—what she COULD earn given her education, work history, and local job market. Document her qualifications and job history to support an imputation argument. Pro Tip: Research median salaries for her profession in your area. Present this data to your attorney. Statistic: Income imputation is granted in 62% of cases where the receiving parent voluntarily reduces income

What if my income increases significantly—can she demand more?

Yes. Either parent can request modification when circumstances change substantially. If your income doubles, expect a potential modification request. Some Dads negotiate caps in their agreements. Pro Tip: Consider negotiating a support ceiling in your divorce agreement—'support shall not exceed $X regardless of income changes.'

What if I have another child with a new partner — does child support decrease?

Having another child does NOT automatically reduce your child support obligation for existing children. Courts prioritize first-born children's financial needs. However, a new dependent can be a factor in modification requests, though results vary significantly by state and judge discretion. Pro Tip: Focus on documented income changes and increased custody time rather than new family obligations when seeking modifications. Statistic: Only 23% of modification requests citing new children result in meaningful support reductions

When does child support end — does it stop at 18 automatically?

Not always. Most states end child support at age 18 or high school graduation (whichever is later). Some states extend support obligations through college (to age 21-23). Medical support for disabled adult children may continue indefinitely. Always check your specific court order and state law for the exact termination date. Pro Tip: File a motion to terminate support 60 days BEFORE your child's 18th birthday to avoid bureaucratic delays.

Updated Jan 2026

Child Support Calculator

Get a realistic estimate based on the Income Shares Model used by most states. Includes custody time adjustments and additional expense calculations.

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Custody Adjusted

Budget Impact

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2 Minutes

Income & Family Information

Enter your details for an accurate estimate

Your State

Your Monthly Gross Income

Before taxes and deductions

Other Parent's Monthly Income

Estimate if unsure

My income varies month to month

Number of Children

Your Parenting Time20%

0% (No overnight visits)50% (Equal time)

Tip: 20% = ~73 overnights per year

How This Child Support Calculator Works

Enter both parents' income

We use gross monthly income (before taxes) for both you and your co-parent to calculate combined family income.

Select your state

Each state has different child support guidelines. We apply your state's specific multiplier and formula type (Income Shares or Percentage).

Adjust for custody time

More parenting time = lower support. We calculate the custody credit based on your percentage of overnights.

Add expenses (optional)

Health insurance and childcare costs are typically split proportionally and added to the base support amount.

Get your estimate

See monthly/annual amounts, budget impact, and per-child breakdown. Download or save for court preparation.

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