Free Child Support Calculator — State-Specific Estimates for All 50 States

Pick your state, enter two incomes, and see what child support looks like under your jurisdiction's formula — no credit card needed

Simple Child Support Calculator

Get a quick estimate of potential child support in under 60 seconds based on simplified state guidelines, without personal information or a credit card.

State: Select State: Alabama, Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, District of Columbia, Florida, Georgia, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming

Number of Children: 1, 2, 3, 4, 5

Your Monthly Income: $

Your Spouse's Monthly Income: $

Percentage of time you will have the children: 0%, 50%, 100%

Fill out your information to begin exploring potential support payments.

Important Disclaimer: This calculator is for educational purposes only and provides only rough estimates that might vary significantly from official state calculations. Official calculations include many additional factors not included here. This tool does not constitute legal advice and should not be relied upon for any important decisions. For accurate calculations, please consult a family law attorney or your state's official child support agency.

How the Child Support Calculator Works

We analyzed the child support statutes for every U.S. jurisdiction. The result is a quick estimate that follows the same decision tree a court would use.

1. Choose Your Jurisdiction

Your state dictates which model applies — income shares, flat percentage, Melson, or hybrid. The dropdown routes you to the right one.

2. Add Financial & Custody Details

Enter annual income for both parents, number of children, and custody split. The engine accounts for shared-parenting adjustments automatically.

3. Read Your Results

See the estimated monthly payment, which parent pays, and context about how your state typically enforces guideline amounts.

The Four Calculation Models Behind U.S. Child Support

Each state chose its own mathematical framework. Knowing which one governs your case tells you whether you need one income figure or two, and how much leverage your custody arrangement gives you.

Income Shares Model (41 states)

Both parents' earnings are pooled, then split proportionally. The noncustodial parent's share becomes the monthly payment.

  • Inputs needed: Both incomes + child count
  • Adjusted for: Health insurance, childcare, parenting time
  • Example: Combined $10K/mo, 2 kids = $1,800 obligation. Parent earning 60% pays $1,080

Percentage of Income (5 states)

Only the noncustodial parent's income matters. A flat percentage is applied — the other parent's earnings have zero effect.

  • Texas: 20% / 25% / 30% / 35% / 40% for 1–5+ kids, capped at $9,200/mo net
  • Wisconsin: 17% / 25% / 29% / 31% / 34% of gross
  • Nevada: 18% / 25% / 29% / 31% + 2% per child beyond four

Melson Formula (3 states)

Adds a self-support reserve — each parent keeps enough for basic subsistence before any dollar goes toward support.

Hybrid & Algebraic (CA, DC, MS)

California's K-factor plugs both incomes + exact timeshare into an algebraic equation.

Not Sure Which Model Applies to You?

The calculator auto-detects your state's model when you select it. You'll see the model name alongside your estimate.

Variables That Move the Number Up or Down

Income, custody, and child count are the three biggest drivers. But courts also weigh secondary factors that can shift the final order 15–30% in either direction.

Which “Income” Your State Measures

Getting the income definition wrong is the #1 reason DIY worksheets produce bad numbers. Key differences:

  • Gross-income states (e.g., Wisconsin) — start with a higher base before any deductions
  • Net-income states — subtract taxes and mandatory deductions first

How Each Additional Child Changes the Math

Adding a second child does not double the obligation.

Insurance Premiums & Childcare Add-Ons

After the base obligation, virtually every state layers on two mandatory add-ons:

  1. Health insurance — the incremental cost of adding the child to a policy
  2. Work-related childcare — daycare, after-school care, summer camp

When Income Exceeds the Schedule

Every guideline has a ceiling. Above it, the judge exercises discretion.

The Overnight Count: Where Custody and Dollars Intersect

Every additional overnight shifts spending from a transfer payment to direct expenditure — and most state formulas reduce the support order accordingly.

How Long Child Support Lasts — and How to Change It

A child support order is a snapshot of two incomes at a single point in time. Life changes. The law accounts for that — but only if you take the right steps.

Triggering a Modification

Every state requires a “substantial change in circumstances.” What counts as “substantial” varies:

What Happens When Payments Stop

Unpaid child support triggers an escalating enforcement toolkit:

Frequently Asked Questions

How close will this estimate be to my actual order?

What counts as “income” for child support?

We split custody 50/50 — do I still owe support?

Can a judge order more than the guideline amount?

My ex is hiding income — what can I do?

How soon after a job change can I request a modification?

This Estimate Is a Starting Point. Get the Complete Picture.

Our full application models custody scenarios side by side, factors in insurance and childcare add-ons, and generates a report you can bring to mediation or your attorney.