Estimate California child support under Cal. Fam. Code § 4055 — Income Shares model, current caps and percentages, with a step-by-step worked example.
| Guideline model | Income Shares |
|---|---|
| Income basis | Net (after-tax) income |
| How it works | Statewide algebraic formula CS = K x (HN - H% x TN), where HN is the higher earner’s net disposable income, H% their share of parenting time, TN combined net income, and K a factor set by income bracket. Multi-child multipliers apply (x1.6 for two children, x2.0 for three). |
| Caps & limits | Statewide uniform guideline (algebraic formula); low-income adjustment applies below statutory threshold |
| Statute / rule | Cal. Fam. Code § 4055 |
| Parameters verified | 2026-07 |
Result: $1,469 per month
California uses the income shares model under Cal. Fam. Code § 4055: both parents’ incomes are combined, a basic obligation is determined, and each parent is responsible for their proportional share. Statewide algebraic formula CS = K x (HN - H% x TN), where HN is the higher earner’s net disposable income, H% their share of parenting time, TN combined net income, and K a factor set by income bracket. Multi-child multipliers apply (x1.6 for two children, x2.0 for three).
California calculates support on net (after-tax) income as defined in Cal. Fam. Code § 4055. Statewide uniform guideline (algebraic formula); low-income adjustment applies below statutory threshold.
Yes. The guideline amount under Cal. Fam. Code § 4055 is presumptive, not absolute - courts may deviate with written findings for factors like extraordinary medical or educational needs, other children supported, or very high income beyond the guideline range.
Apply through the California child support agency or the family court in your county. Existing orders can be modified on a substantial change in circumstances - typically a significant income change, job loss, or a change in custody. The official calculator/worksheet is linked on this page (childsupport.ca.gov).
Estimate only — not legal advice. Based on California guidelines (Cal. Fam. Code § 4055), last verified 2026-07. Courts may deviate. For an official figure use the official California calculator.