How we build our calculators and guides

Calculators

• The formula is on the page. Every calculator shows the formula it uses and a worked example.
• Tested before publishing. Each calculation is a separate function with automated tests that check it against standard values — for example, a ₹5,000 SIP for 10 years at 12% must give ₹11,61,695.
• Indian conventions. FDs and RDs compound quarterly like Indian banks; loan EMIs use the reducing balance; SIP instalments are taken at the start of the month.
• Assumptions are labelled. Defaults such as 6% inflation are shown as editable assumptions, not facts about the future.
• The same maths as the app. Where Spendly has the same feature (EMIs, FDs, XIRR, Safe to Spend), the calculator uses the app’s own code, so the numbers match.

Guides

• Steps are checked in the real app. Guides about another company’s app (CAMS, Groww, Zerodha, Binance) show the date the steps were last checked. Menus change; if one has moved, tell us and we fix it.
• Independent. Spendly is not affiliated with the companies whose apps it describes; their names are their trademarks.
• Only what Spendly really does. Guides about Spendly describe features exactly as they work today — for example, Spendly reads your bank’s alert messages, never your UPI apps or your bank login.

Sources

Facts come from primary sources: the Reserve Bank of India, SEBI, AMFI, the Income Tax Department, the Ministry of Statistics, NPCI, and the registrars and platforms themselves. Each page lists the sources it relies on.

Updates and corrections

• Every page shows when it was published and last updated. The date changes only when the content does.
• Guides about other apps are re-checked every quarter; rates and rules (tax, deposit limits) are reviewed at least once a year.
• Found a mistake? Contact us — corrections are made as soon as they are confirmed.

Use of AI

Drafts may be prepared with the help of AI tools. Nothing is published until the Spendly team has checked it against the sources above and, for calculators, until the tests pass.

Education, not advice

The calculators and guides explain how money works; they do not recommend what you should buy or sell. For decisions about your own situation, consider a SEBI-registered investment adviser.