2026 Child Support Guidelines & Model Benchmarks
Statutory formulas and judicial child support schedule models across all 50 states
Income Shares Model
39 States
Combines both parents gross/net income
Percentage of Income
10 States
Flat or graduated % of obligor earnings
Melson Hybrid Formula
3 States
Delaware, Hawaii, Montana models
Shared Custody Threshold
35% – 40% Overnights
Triggers substantial parenting-time credit
Self-Support Reserve
$1,200 – $1,600 / mo
Guaranteed minimum subsistence floor
Substantial Change Rule
15% – 20% Variance
Standard threshold to modify support order
Modify Child Support — Not Just a Calculator
Skip the scattered calculators. Get a guided, step-by-step child support plan that walks the full lifecycle — from filing to a new order — with a printable takeaway and a gap/eligibility check you can act on. Every figure statute-cited to your state’s guideline.
Full U.S. coverage
Every state + D.C., one hub.
Statute-cited
Each figure links to its state law.
Official schedules
47 states loaded from agency tables.
3 models explained
Income Shares, Percentage & Melson.
Go beyond a basic estimate
Three planning tools that set ChildSupportFig apart — work backwards, model a life change, and compare every state at once.
Reverse calculator
Target a monthly payment → see the income it implies under your state’s guideline.
Open →⇄What-if simulator
Compare two scenarios — a raise, custody change, or added costs — side by side.
Open →≣Cross-state compare
See how the same income produces different obligations across all 50 states + D.C.
Open →20262026 rule changes
Passport revocation for arrears, NY $193k cap, MA $450k, WA $50k — dated and sourced.
Open →⇅Modification check
Do you meet your state’s threshold to change the order? 51-state go/no-go with statutes.
Open →✚Medical expense splitter
Divide braces, therapy, and out-of-pocket health costs under state law with 30-day demand notice.
Open →Child support — quick answers
Is this child support calculator free?
Yes. Every state estimator, the reverse calculator, the what-if simulator, and the cross-state comparison are free and ad-supported.
How accurate are the estimates?
States with a verified statutory or agency schedule use real published rates. Other states are clearly labeled “model estimate” and use a reference schedule until verified against the official guideline.
Does child support law differ by state?
Yes. Each state uses one of three models — Income Shares, Percentage of Income, or the Melson Formula — with its own income definition and schedule.
Select your state
Green = official schedule loaded. Red = model estimate pending verification.
How U.S. child support models differ
- Income Shares (41 states + D.C.): both parents’ incomes are combined, matched to a schedule, then split proportionally — plus child-care and health-insurance add-ons and a parenting-time credit. in-depth look →
- Percentage of Income (6 states): a flat or graduated percentage of only the paying parent’s income — the simplest model, shown here with verified statutory rates. detailed breakdown →
- Melson Formula (3 states): Income Shares plus a self-support reserve and standard-of-living adjustment (Delaware, Hawaii, Montana). thorough walkthrough →
Guides & articles
Plain-English explainers for parents and payers — each links straight to the calculators.
What Is Child Support?
A plain-English primer on what child support is, who pays it, what it covers, and how it differs from other family-law obligations.
The mathHow Is Child Support Calculated?
The three U.S. guideline models explained — Income Shares, Percentage of Income, and the Melson Formula — and the inputs that move the number.
Model deep-diveWhat Is the Income Shares Model?
The most common U.S. child-support model, explained: combined income, the basic-obligation schedule, proportional splitting, and add-ons.
Model deep-diveWhat Is the Percentage of Income Model?
The simplest U.S. model: a flat or graduated percentage of the paying parent’s income. How the six states apply it.
State resources, on every page
Each state calculator now includes a resources section with how that state calculates support, how to open or modify a case, illustrative examples, frequently asked questions, and direct links to the official statute and child-support agency. Where we are still verifying a section against primary sources, it is clearly marked “coming soon.”
Compare & learn
See how the same income produces different obligations across states on the cross-state comparison tool, browse the full child support by state table, read the model guides, or start with the basics articles.
More planning tools & guides
Deeper tools for specific situations — each grounded in state law and linked from the calculators above.
Parenting Time & Overnights
Calculate annual overnights and 50-state shared physical custody discounts.
Life changeIncome Change Simulator
Model how a raise, job loss, or new child changes your obligation.
High incomeHigh-Income Child Support
Above-guideline caps and deviations (NY, MA, WA and more).
Post-18Child Support After 18
When support continues for college or disability.
Multi-stateInterstate Cases (UIFSA)
Which state decides when parents live in different states.
DeadlinesStatute of Limitations
How long arrears and enforcement actions can last.
WorksheetChild Support Worksheet
A fillable worksheet to organize your own numbers.
MonitorReview Reminder
Set a reminder to revisit your order when life changes.
SourcesCitation Packs
Per-state statute and agency citations in one place.
Child Support Legal Next Steps & Financial Planning Hub
Statutory guidelines, arrears enforcement deadlines, custody calculators, and court modification tools
Explore 50-state arrears collection limits, interest rates on past-due child support, and court enforcement rules.
Determine if an income change, job loss, or shift in custody meets your state's threshold for a legal support adjustment.
Calculate exact annual overnights and parenting time percentages to qualify for statutory shared-custody credits.
See how courts calculate support when combined parental income exceeds state statutory guideline caps.
Calculate statutory compound interest assessed by state child support agencies on delinquent support balances.
Estimate disposable earnings and federal CCPA statutory limits on child support wage withholding.
Hero photo by Cheung Yin on Unsplash.
Why Parents & Family Law Mediators Rely on ChildSupportFig
Most online legal calculators function as lead-capture funnels designed to harvest sensitive family data for attorney retainers. ChildSupportFig was built as an open, private educational utility providing objective mathematical clarity before entering court.
Zero Minor-Child Data Harvesting
Commercial legal portals demand child names, birthdays, and contact info to sell to divorce attorneys. ChildSupportFig runs 100% locally in your browser. Not a single income digit or family record ever touches a remote server.
Statute-Cited Title IV-D Guideline Schedules
Every calculation references codified state statutes — from California Fam. Code § 4055 algebraic curves to Texas Fam. Code § 154.125 percentages — directly aligned with state Child Support Enforcement (IV-D) tables.
Three Distinct Judicial Models Mapped
Child support cannot be calculated with a one-size-fits-all formula. We accurately separate and model Income Shares (39 states), Percentage of Obligor Income (10 states), and the Delaware/Hawaii Melson Formula.
Parenting-Time Offsets & Self-Support Floors
Real child support determinations account for shared physical custody thresholds (overnights), mandatory health insurance apportionments, childcare add-ons, and statutory self-support subsistence reserves.