Transparent by design
The number comes before the opinion.
Every public calculator starts with a defined formula and the values you enter. Koala can explain the result or help test a scenario, but it does not get to rewrite the arithmetic.
Methodology reviewed 28 August 2026.
One formula, multiple views
Quick and Detailed change the amount of explanation, not the underlying result. Public pages, saved calculations and Koala tools are expected to use the same canonical calculator definition and formula version.
Inputs and assumptions stay separate
A business fact entered by the user is not silently replaced with a market benchmark. Where a calculator needs an assumption, the page identifies it and the user can test a different scenario.
Exact arithmetic is not certainty
A deterministic formula can be exact for the values supplied without predicting customer behaviour, future demand or a regulatory outcome. MarginKoala labels those boundaries instead of turning a scenario into a promise.
Saved evidence has a trust state
Where a matching server-side formula exists, saved browser output is recomputed before it can become verified evidence. Unsupported or invalid domains remain visibly unverified rather than being promoted by appearance alone.
What each calculator page includes
- A plain-English business question and definition.
- The interactive worked example using your own figures.
- Formula, assumptions and calculation mechanics.
- Genuine frequently asked questions where useful.
- Related calculators and a clear route to keep the result.
- A visible review date and canonical page address.
Common mistakes to avoid
- 1Mixing inputs from different periods, currencies or accounting bases.
- 2Treating a deterministic scenario result as a forecast or guarantee.
- 3Using a tax, fee or market assumption that has not been checked for the business and date.
Follow the definitions
The calculator library is organised by the business decision being made. Related links connect formulas that share inputs or naturally form the next step — without creating duplicate calculator logic.
