How Michigan calculates child support
- Each parent’s monthly net income (after taxes and mandatory deductions) is used. A parent who supports other minor children has their income reduced by a multiplier, for example 83% for one other child.
- The parents’ incomes are combined and the General Care Equation from the formula’s tables gives each parent’s base support according to their share of the family income.
- A parent with net income at or below the Low Income Threshold ($1,255 a month) owes 10% of their income; just above it, a transition equation can lower the amount.
- The Parental Time Offset equation then adjusts for the overnights the children spend with each parent, and the parent who owes more pays the difference.
- The paying parent also pays their share of the children’s average ordinary medical expenses ($200 a year per child).
What the calculator asks
- How many children do you have together that the support is for?
- How many overnights a year will the children spend with you?
- Your net income per month
- The other parent’s net income per month
- How many other minor children (not with the other parent) do you have a legal duty to support?
- How many other minor children does the other parent have a legal duty to support?
- Does a child receive Social Security or other dependent benefits because of a parent?
It never asks for names, Social Security numbers or account numbers, and your answers are not saved.
What the estimate leaves out
- Health care insurance premiums for the children (MCSF 3.05)
- Child care expenses (MCSF 3.06)
- Additional (extraordinary) medical expenses above the ordinary amount
- A child’s Social Security or other dependent benefits credited against support (MCSF 3.07)
- Children in the custody of someone other than a parent (MCSF 4.01)
- Deviations the court may make, including for extremely high family incomes (MCSF 1.04 and 3.02(E))
When a situation is outside what the calculator covers, it says so and points you to the official worksheet instead of guessing.
Official sources
- 2025 Michigan Child Support Formula Manual (effective January 1, 2025)
- 2025 Michigan Child Support Formula Supplement (Low Income Threshold, General Care Support Tables, schedules)
- Michigan Courts, Michigan Child Support Formula
MiChildSupport Calculator (State of Michigan) →
Ready to estimate? The calculator shows each worksheet line so you can check it against the official form.
Open the Michigan calculator →An estimate from the published guideline formula, not a prediction of a court order. The official court worksheet and the court’s decision control. General information, not legal advice. LawCat is not a law firm.