Methodology & Data Sources

Data Sources

PlainChildSupport's state guideline data comes from official sources:

The Three Child Support Formula Models

U.S. states use three fundamentally different approaches to calculate child support:

  • Income Shares Model — Used by the majority of states (~40 states). Both parents' incomes are combined to estimate total child-rearing costs. Each parent contributes proportionally to their share of combined income. The custodial parent's share is presumed spent directly on the child.
  • Percentage of Income Model — Used by states like Texas, Illinois, and Wisconsin. Support is a fixed percentage of the non-custodial parent's income only. Texas uses 20% for 1 child, 25% for 2, 30% for 3, etc.
  • Melson Formula — Used by Delaware, Hawaii, and Montana. A more complex hybrid that first ensures each parent retains enough income for their own basic subsistence needs before calculating the child support obligation. The Melson Formula adds a self-support reserve and a standard of living adjustment that the other two models do not include.

How Our Calculators Work

Interactive calculators (available for the 10 largest states) use each state's published income schedule percentages or worksheet formulas. For Income Shares states, we use approximate schedule percentages derived from published income tables. For Percentage of Income states, we apply the statutory percentages directly.

All results are labeled as estimates. Real child support calculations involve precise line items, deductions for health insurance and childcare, and judicial discretion that no online tool can fully replicate.

State Profile Pages

For all 50 states plus DC, PlainChildSupport provides: formula model used, statutory percentage or schedule reference, modification threshold, links to the official state guideline document or calculator, and state-specific notes on deviations, adjustments, and special circumstances. Each state profile includes the relevant statute citation so users can verify the guidelines directly in the state code.

Limitations

  • Child support calculations are complex — the interactive calculator produces estimates only
  • Actual orders depend on judicial discretion, complete financial disclosure, and local court practices
  • State guidelines change through legislation — verify current guidelines with an attorney
  • This site is for informational purposes only and does not provide legal advice

How We Research State Guidelines

Child support guidelines are set by state legislatures and published in state statutes. We research each state's current guidelines by reviewing the relevant state code sections, official child support enforcement agency publications, and guideline worksheets published by state courts. For the Income Shares model, states publish income-sharing tables that map combined parental income to presumptive child support obligations at various income levels and numbers of children.

Our research process involves reviewing primary legal sources (state statutes, court rules, administrative regulations) and cross-referencing with secondary sources (NCSL comparative analyses, state bar association guides, legal aid publications). Any discrepancy is resolved in favor of the primary source.

Data Accuracy Commitment

PlainChildSupport strives for accuracy in presenting state guideline information and calculator formulas. However, child support law is complex and changes frequently through legislative action. We encourage users to verify current guidelines with their state child support enforcement agency or a licensed family law attorney. If you find any data that appears outdated or incorrect, please contact us so we can investigate and update.

Contact

Questions about our methodology or found an error? Reach us at hello@plainchildsupport.com or through our contact page.