Methodology

What our calculators do, what they simplify, and where the numbers come from.

Child support

Each state page applies that state's guideline model as published in statute or court rule:

• Percentage-of-income states: we apply the state's published percentages by number of children to the paying parent's income, on the income basis (gross or net) the state specifies. Where a state applies its guideline to net income, we approximate net income as 75% of the gross figure you enter.
• Income-shares states: the exact basic-obligation schedules are long lookup tables that vary by state. We approximate them with a combined-income percentage curve derived from the Betson-Rothbarth economic estimates most state schedules are built on (17% of combined income for one child, scaling to ~35% for six, with the marginal rate halved above $12,500/month combined). This produces figures close to most state tables in the middle of the income range and is clearly labeled an estimate.
• Melson states (Delaware, Hawaii, Montana): the full Melson computation requires inputs beyond a simple calculator; we use the income-shares approximation and say so on those pages.
• Adjustments: children's health-insurance premiums and work-related childcare are added to the obligation and shared. Parenting time above ~20% of annual overnights earns a credit that scales toward 50% at equal time — a simplification of the varied state formulas.

Alimony

Where a state has a statutory formula (e.g., Illinois, New York) or statutory cap (Texas), we apply it. In discretionary states we apply the American Academy of Matrimonial Lawyers (AAML) guideline — 30% of the payer's gross income minus 20% of the recipient's, with the recipient's total income capped at 40% of combined income — which practitioners widely use for ballpark estimates. Duration estimates use statutory duration schedules where they exist and marriage-length heuristics where they don't.

Divorce costs

Filing fees come from state court fee schedules (county-typical where fees vary by county). Attorney rates and total-cost ranges come from published surveys of family-law practitioners (Martindale-Nolo and comparable industry surveys). Situation multipliers (contested status, children, representation path) reflect the cost drivers those surveys report.

What these calculators are not

They are not legal advice, not official guideline worksheets, and not a prediction of what a judge will order. Courts deviate from guidelines for many reasons. Use our numbers to get oriented, then verify with your state's official calculator (linked on each page where one exists) or a licensed attorney.

Updates

State guidelines change — percentage tables are revised, caps are indexed, statutes are amended. We review every state's parameters quarterly and date-stamp each page with its last review. If you spot an outdated figure, email us and we'll fix it.