Methodology and data sources
How the reviewed calculator collection is selected, where Australian figures come from, and what we deliberately refuse to guess.
What the reviewed collection includes
CalcAussie's public directory contains 57 calculators selected for the current reviewed collection. Those are the calculator pages available through category pages and submitted in the search sitemap. Unreviewed calculator source code can remain in development, but its pages are unavailable to the public until the method, examples, assumptions and limitations pass an individual review.
Calculations run in your browser
Calculator inputs are processed on your device rather than submitted to CalcAussie for calculation. We do not store the figures you enter into a calculator. This keeps the tools fast and means you do not need an account to use them.
Methods, assumptions and limitations
Pages in the reviewed collection describe the calculation method in plain language and identify material assumptions or limitations where they affect the estimate. The amount of explanation varies with the tool: a simple-interest estimate does not need the same treatment as a tax, loan or employment estimate. When a calculation simplifies a real-world rule, we aim to say so rather than present the result as exact for every circumstance.
Rates, thresholds and the financial year
Tax-year-dependent Australian figures such as resident income tax brackets, the Medicare levy setting used by our estimates, HELP repayment thresholds and the super guarantee rate are kept in a central configuration so related calculators use consistent values. We review those figures against current Australian Government sources and display the applicable financial year on affected pages.
Official sources
For regulated or time-sensitive Australian figures, we prefer primary or government sources such as the Australian Taxation Office, Study Assist, Moneysmart, Fair Work and state revenue authorities. Priority financial calculator pages also link to the relevant source material so readers can check the assumptions directly.
What we will not invent
Some figures genuinely differ by state, provider or personal circumstance, including conveyancing fees, lender charges, electricity tariffs and water pricing. Where a reliable universal figure does not exist, we prefer a clearly labelled editable input or an explicit limitation instead of a made-up national average.
Rounding
- Currency is displayed in Australian dollars and generally rounded for display while the underlying calculation keeps its working precision.
- Percentages are shown to a sensible number of decimal places for the quantity being measured.
- Dates use Australian conventions (DD/MM/YYYY) and financial-year-dependent calculators use the Australian 1 July to 30 June financial year.
Review and checking
Calculation logic is kept separate from much of the interface so formulas can be reviewed and checked consistently. The project also includes automated test and SEO-validation scripts that can be run during development. Material rate or formula changes to the reviewed collection are checked with the affected source, assumptions and visible wording in view.
Editorial depth and maintenance
The reviewed collection is supplemented by category guidance and a source-backed Australian guide library that explains how to choose inputs, compare scenarios and recognise the limit of a numerical result. Material review work is recorded in the public review log. A calculator is not added to the reviewed collection only to repeat a search phrase; it must perform a distinct calculation or support a distinct practical decision.
Limits
These are estimating tools, not lodgement, advice or compliance software. Read the disclaimer before acting on any figure, and tell us about errors through the contact page. Our editorial and corrections policy explains how we handle updates and reported errors.