How We Check Our Numbers

Our rules

• Every calculator shows its formula and a worked example on its page, and automated tests check that the calculator gives exactly those numbers.
• Figures that change by law or order (rates, charges, limits, fees) come from the official notice, with the date we checked it. The page shows “Rules last reviewed”.
• We don’t guess. If we can’t find the official text, we don’t publish the figure: the income tax calculator, for example, waits for the Finance Act’s rate schedule.
• Where a figure is only reported (for example a meter rent quoted in the news) the page says so, and you can change any pre-filled figure to match your own bill or notice.
• Health pages use published medical formulas and guidance (ACOG, NHS, WHO, the Mifflin–St Jeor equation) and say clearly that they are not medical advice.
• What you type never leaves your device. No inputs or results are sent to a server, put in links or recorded in analytics.

How every change is tested

Before anything ships, the calculation tests, a type check and a production build must pass, and a browser test opens every calculator in Bangla and English, checks an empty form shows an error and checks a real calculation shows a result.

When each rule was last reviewed

Calculators and guides whose figures depend on a rule, order or notice, newest review first:

Calculators

Guides

When rules change

We re-check figures when the source changes: after each budget (from July), each BERC tariff order, each Sanchayapatra rate notice (January and July), each BCS circular and each board notice. Until a page is updated, the date above tells you how fresh it is, and the official notice always wins.