Updated for 2026 state guidelines
Child support numbers you can check
Child support rules are public law, but the math behind them is hard to find and easy to get wrong. This site runs the real state formulas and shows its work. Every rate, cap, and table links to an official source, with the date it took effect and the date we last checked it.
Everything here is an estimate, not legal advice. The court or state agency calculation controls.
Start here
Child support calculatorSee which guideline model all 50 states and DC use, compare a standard scenario across them, and run a full estimate for any of the 51 jurisdictions.Open the calculator →State calculators
All 51 jurisdictions have full research packs: the current formula, the current tables, a worked example, and the quirks that trip people up. Each jurisdiction carries four tools: child support, arrears and interest, wage garnishment limits, and alimony or spousal support.
Coverage includes all 50 states plus Washington, DC. Each research pack is reviewed against official worksheets and primary legal sources.
51
Jurisdictions mapped: 50 states plus DC
51
Jurisdictions with full calculators: support, arrears, garnishment, alimony
412
Official sources cited, each with a checked date
Parenting time and money tools
Overnights drive many support formulas, so the schedule tools and the money tools share the same math. All of them run in your browser; nothing you type is stored or sent anywhere.
- Parenting time calculatorCount overnights for 10 common schedules and see the true percentage split.Open the tool →
- Custody schedule generatorLay a rotation over a real calendar and download it as a free .ics file.Open the tool →
- Custody schedule libraryTen patterns like 2-2-3 and week on week off, each with day-by-day math.Open the tool →
- Holiday schedule builderLayer 12 holidays like Thanksgiving and winter break over any rotation.Open the tool →
- Expense split calculatorDivide childcare, medical, and school costs in proportion to income.Open the tool →
- Who claims the child on taxesWhat the 2026 Child Tax Credit is worth and how Form 8332 moves the claim.Open the tool →
- Guides libraryTen short guides to the formulas, income rules, and schedule math.Open the tool →
- High-income child support capsWhat happens above the guideline ceiling in 6 states with newly effective caps.Open the tool →
- Child support by incomeWhat $500 to $2,000 a week looks like in 5 states, shown as scenarios, not one number.Open the tool →
How we keep the numbers honest
A number without a source is a guess. Ours come from statutes, court rules, and official guideline tables, and each page lists exactly which ones. When a state has no formula, we say so instead of inventing one. When a rule changes, the fix gets a dated entry in the update log, never a silent edit.