California Child Support Calculator

At $6,000 per month in combined monthly net disposable income, California's guidelines produce roughly $810/month for 1 child, $1,296/month for 2 children, $1,620/month for 3 children, $1,863/month for 4 children. These figures come from running California's own guideline formula, but they hold several things constant -- assumes the higher earner has 65% of the combined income shown, the calculator's default 20% higher-earner time-share, and no hardship deduction. Your actual number depends on both parents' incomes, your parenting-time schedule, and add-on costs like childcare and health insurance, so run the calculator for your own case.

California uses the Income Shares model. California computes support with the statutory algebraic formula CS = K[HN − (H%)(TN)], where K is an income- and time-share-based factor, HN is the higher earner's net income, and TN is the parents' combined net income. The one-child result is then scaled up for additional children.

California's guideline runs on net monthly disposable income (both parents). That distinction matters: entering gross income into a formula built on net income (or the reverse) produces a materially wrong figure. Most states count income from essentially any regular source -- wages, self-employment, bonuses, commissions, rental and investment income, and many benefits -- not just salary.

Not necessarily. In California: the higher earner's parenting-time percentage (H%) directly reduces or increases the result. Because the guideline also weighs each parent's share of income, a significantly higher earner can still owe support at an even time split.

This calculator's core formula has been verified against the primary source, with any unimplemented rules listed openly rather than hidden. It implements the guideline in effect as of 2024-09-01, and a human last checked it against the primary source on 2026-08-12. Sources: Cal. Fam. Code § 4055 (as amended by SB 343, Stats. 2023, ch. 213). It is still an estimate, not a court order -- a judge can order a different amount, and this is not legal advice.

The California guideline this calculator implements took legal effect on 2024-09-01. States revise their guidelines periodically -- federal rules require each state to review its guidelines at least once every four years -- so a figure from an older calculator or article may reflect a superseded rule.

The § 4055(b)(7) low-income adjustment is not applied. Net disposable income is entered directly rather than computed from gross income under §§ 4059-4060, so the result is only as accurate as the user's net figure. If any of these apply to your case, treat the estimate as a starting point and confirm the figure with an attorney, a mediator, or California's official worksheet.

Yes. The figure produced by California's Income Shares guideline is presumptive, not mandatory: a court can order a different amount when applying the guideline would be unjust or inappropriate for the specific case, and generally must state its reason on the record. Common grounds include extraordinary medical or educational expenses, a child's special needs, or costs the formula does not capture. California's guideline is set out in Cal. Fam. Code § 4055 (as amended by SB 343, Stats. 2023, ch. 213).

You have to file for a modification -- a change in your circumstances does not change what you owe on its own. California, like most states, requires a substantial change in circumstances: a significant involuntary income change, a change in the parenting schedule, or a material change in the child's needs. Until a court or the state child support agency issues a new order, the existing amount stays fully enforceable and arrears keep accruing, and a modification is generally not applied retroactively before the date you filed -- so filing promptly matters.