Child Support Estimator (Australia)

Estimate Australian child support payments using income and care percentage based on the Services Australia formula, free and instant in your browser.

100% FreeRuns in your browserBasic

How to use this calculator

Enter Values

Your taxable income ($/year)

Minimum 0

Other parent's income ($/year)

Minimum 0

Self-support amount ($/year)

Minimum 0

Your nights of care per year (0–365)

Range 0–365

Costs of the children ($/year)

Minimum 0

Enter your values and press Calculate to see results.

Before you rely on this: First-pass guide only. Verify safety-critical or regulated work against the relevant standards, your project requirements and a qualified professional.

How to use this calculator

Enter both parents' taxable incomes and the current self-support amount.
Enter your nights of care per year and the Costs of the Children figure (both from Services Australia).
Press Calculate for a rough estimate of who pays whom and how much.

How it works

This follows the basic Australian (Formula 1) method. Each parent's child support income is their taxable income minus the self-support amount; combined, these give each parent's income percentage.

Your care percentage is converted to a cost percentage using the official Care and Cost table. Your child support percentage is your income percentage minus your cost percentage — if it's positive you pay, if negative you receive. The amount is that percentage of the Costs of the Children.

Worked example

Incomes $100k and $50k, 146 nights' care. Income percentage ≈ 77.8%, cost percentage 35% (40% care), so child support percentage ≈ 42.8%. Against $20,000 costs that's about $8,556 per year.

Tips

The basic formula here ignores relevant dependent children and multiple child support cases.
Use your adjusted taxable income, not just your salary.

Frequently asked questions

Is this the official assessment?

No. It's a rough estimate only — just Services Australia can make a formal assessment. Use current figures and get an official assessment before relying on any number.

Where do I find the self-support amount and Costs of the Children?

Both are published by Services Australia and updated each year.

Related tools

Explore more in Family, Parenting & Custody.

Cite this tool

Zerdly. (2026). Child Support Estimator (Australia). Retrieved from https://www.zerdly.com/tools/child-support-estimator-au/

Tip: Enter any known values to calculate the remaining results.

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