Wisconsin Child Support Calculator

Wisconsin uses the Percentage of Obligor Income model. Wisconsin uses a percentage-of-income standard applied to the gross income of the paying parent: 17% for 1 child, 25% for 2, 29% for 3, 31% for 4, 34% for 5+. Shared-time payer adjustment applies when each parent has placement at least 25% of the time.

Wisconsin's guideline runs on gross income (paying parent only). 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. Wisconsin calculates support as a percentage of the paying parent's own income, so parenting time is not a direct input to the base formula the way it is in income-shares states -- custody arrangements are generally handled as a reason to deviate from the guideline rather than as a variable inside it.

Yes. The figure produced by Wisconsin's Percentage of Obligor Income 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.

You have to file for a modification -- a change in your circumstances does not change what you owe on its own. Wisconsin, 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. In Wisconsin, modifications are handled through Wisconsin Child Support Program — DCF.

Wisconsin publishes it directly: "Child Support Tools & Worksheets — Wisconsin DCF". This site's calculator is a fast estimate built on the same published guideline, not a replacement for the official form -- a court filing generally requires the state's own worksheet. The link is in the Wisconsin Resources section on this page.