Editorial Policy

CalcPad's goal is simple: every calculator should give the right answer and explain how it got there. This page describes how we build and check them.

Formulas come from published standards

Each calculator uses a well-established, published formula, such as the standard amortization formula for loans and mortgages, the compound interest formula, or the Mifflin-St Jeor equation for calorie needs. The formula is shown and explained on the calculator's page so you can check the math yourself.

How each calculator is checked

• The calculation logic is kept separate from the page design and tested against worked examples with known answers, including edge cases such as zero interest rates or division by zero.
• Example figures quoted in the explanations are recalculated before publishing.
• Explanations and FAQs are drafted with the help of AI tools, then reviewed and edited by the CalcPad team for accuracy before they are published.
• Each page shows the date it was last updated.

Limits of our calculators

Results are estimates for general information. Financial calculators do not know your full situation, tax rules differ between countries, and health calculators cannot replace advice from a doctor. Where a calculator only applies to one country, such as US capital gains tax, the page says so.

Corrections

If you find a wrong result or an error in an explanation, please email [email protected] with the page address and the values you entered. We investigate every report, fix confirmed errors, and update the page's "Last updated" date.

Independence

CalcPad is funded by advertising. Advertisers have no influence over our calculators, formulas, or explanations, and we do not accept payment to change results or recommend products.