How we verify

Tax tools are only as trustworthy as the numbers inside them, and most calculators hide those numbers in the code where nobody can check them or tell how old they are. We do the opposite.

Every rate lives in a dated module

Every tax rate, threshold, bracket and country fact used anywhere on this site lives in a typed “rules module”, never hard-coded inside a tool. Each module carries a lastVerified date and a list of official source URLs (the ATO, the legislation, the destination’s revenue authority). That date is what you see at the bottom of every tool: “Rates and rules last verified: …”. When a tool computes your number, it reads it from these modules, so the figure and its provenance are always the same object.

What we’re not sure of, we flag

Some figures move constantly or are genuinely uncertain, HECS repayment thresholds under the 2025 reform, state land-tax surcharges, proposed measures like Division 296, foreign exchange rates, destination tax details. Rather than present a confident number we haven’t re-checked, we mark it indicative in the rules module, and the tool shows an indicative badge next to it. A machine-readable list of every such figure, with its file location and the official source to check, is generated as VERIFY.md in the codebase.

When the law moves, your results go stale

The rules engine has a version. Every change is recorded in the changelog, tagged with who it affects. When a change touches a tool you’ve completed, your stored result is marked stale and the Rule Change Radar surfaces it against your profile with a plain line on what it means for you and a prompt to re-run.

What verification does not mean

It does not mean we are the ATO, or that our figures are current at the moment you read this, or that they fit your facts. Laws change between our verification date and your departure; individual circumstances decide outcomes that no calculator can see. Treat everything here as a well-sourced starting point for a conversation with a registered professional, not as the final word.