How we calculate
Every ClearCalc calculator is built from published Australian rules and rates. This page explains where our numbers come from, how we keep them current, and what our estimates do and don't include.
Our sources
- Income tax, Medicare, HELP and PAYG withholding: Australian Taxation Office (ATO) tax rates, offsets, repayment thresholds and withholding schedules.
- Superannuation: ATO contribution caps, the Superannuation Guarantee rate, Division 293 and government co-contribution thresholds.
- Stamp duty and land tax: each state and territory revenue office, including first home buyer concessions.
- Centrelink payments, Age Pension, Child Care Subsidy and Paid Parental Leave: Services Australia and the Department of Social Services.
- Private health insurance rebate and Medicare levy surcharge: the ATO and privatehealth.gov.au.
- Pay, leave and penalty rates: the Fair Work Ombudsman and the National Employment Standards.
- Home lending: APRA's serviceability buffer guidance and common lender practice. Lenders set their own policies, so borrowing power and LMI figures are indicative.
- Energy prices: the Australian Energy Regulator's Default Market Offer, the Essential Services Commission's Victorian Default Offer, and published retailer averages.
How we keep figures current
We review every calculator at least once a year after the 1 July changes, and again whenever a rate it relies on changes, such as Centrelink indexation in March and September or a state budget. Each page shows when it was last reviewed. Rates in this version are for the 2026–27 financial year and were last reviewed in October 2026.
Assumptions we make
- Unless a calculator says otherwise, we assume you are an Australian resident for tax purposes.
- Loan calculators use standard amortisation with interest charged at the same frequency as repayments, and assume the rate doesn't change.
- Results are rounded to the nearest dollar or cent for display. Official calculations, such as PAYG withholding, may round differently at each step.
- Where a figure depends on your circumstances, like living expenses or energy rates, we start with a typical value and let you change it.
What our results are and aren't
Our calculators give general estimates. They don't consider your full personal situation and aren't financial, tax, credit or legal advice. For important decisions, check with the relevant agency, your lender or a licensed professional.
Corrections
If you spot something that looks wrong, such as a rate that has changed, please tell us. We check every report and fix confirmed errors as quickly as we can, usually within a few days.
Independence
ClearCalc is independent and free to use. We may earn money from advertising and, on some pages, from clearly labelled partner links. That never changes how a calculator works or the results it shows.