Free estimate · Illinois
Illinois Child Support Calculator
A free estimate under Illinois's guidelines, with the math shown line by line.
- Guideline model
- Income shares based on standardized net income
- Effective
- 2026-03-20
- Source
- 750 ILCS 5/505
This is an estimate for information only — not legal advice, and not a court calculation. Judges can and do deviate from guideline amounts. For the number a court would use, see 750 ILCS 5/505.
This number is a snapshot. Child support depends on parenting time, and parenting time drifts — swapped weekends, changed holidays, summer schedules. Vireo keeps the custody calendar, messages and shared expenses in one timestamped record, so what actually happened is never a matter of memory.
See what Vireo tracks →How Illinois calculates child support
Determine each parent's monthly net income; combine net income; select the basic obligation from the 2026 schedule by combined net income and child count; allocate by each parent's percentage share; add allocated child care, health insurance, extraordinary health and allowed school/activity expenses; subtract direct payments. Shared physical care uses each parent's obligation times 1.5 and the other parent's percentage of overnights, then offsets.
How income is counted: Statutory gross income from all sources, converted to net income by individualized deductions or the standardized tax amount; the 2026 conversion table supplies standardized net-income values.
Source: 750 ILCS 5/505 · Effective 2026-03-20
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