Child Support Estimator
Estimate child support payments using the real Services Australia formula for 2025-26. Uses the cost-of-children table, self-support amount ($28,463), and official care percentage bands.
This calculator provides estimates only. For official assessments, use these government resources:
- Services Australia — Child Support
- Family Relationships Online — free advice, mediation referrals (1800 050 321)
- Federal Circuit and Family Court of Australia
- Legal Aid — free or low-cost legal help (available in every state)
How this calculator works
This calculator applies the real Services Australia child support formula for 2025-26. It deducts the self-support amount ($28,463) from each parent's adjusted taxable income, calculates income shares, looks up the cost of children in the official table based on combined income and age group, then adjusts for your care percentage band. The result is an annual and fortnightly estimate of child support payable.
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Frequently Asked Questions
How is child support calculated in Australia?
Services Australia uses an 8-step formula. It takes each parent's adjusted taxable income, subtracts the self-support amount ($28,463 for 2025-26), works out each parent's income share, applies the cost-of-children table for the combined income and age group, then adjusts for the care percentage each parent provides.
What is the self-support amount?
The self-support amount for 2025-26 is $28,463. This is deducted from each parent's adjusted taxable income before calculating child support, recognising that each parent needs a basic amount to live on.
Does the number of nights really matter?
Yes — nights per fortnight determine your care percentage band, which directly affects how much child support is payable. Even a one-night difference can move you into a different band with a significant dollar impact.
Is this an official assessment?
No. This is an estimate based on the published Services Australia formula and rates. Your actual assessment may differ based on factors like other dependants, multi-case caps, and any departure decisions. Use this as a guide and contact Services Australia for an official assessment.
Related Calculators
Care Percentage Calculator
Convert nights per fortnight into the official Services Australia care percentage and band. See how your care arrangement affects child support and Family Tax Benefit.
Shared Expenses Splitter
Split shared child-related expenses fairly between separated parents based on income. Cover school fees, medical costs, activities, childcare, and more.
Child Support Change Calculator
See how changes in income, care percentage, or number of children would affect your child support assessment. Compare your current and proposed scenarios.
