How we calculate and verify

Every YogiCalc calculator is meant to give you an answer you can check. This page explains where our formulas and rates come from, how we test each tool, how often we review it, and what to do if you find a mistake.

1. Every result comes from a stated formula or rule

Each calculator implements a published formula, a statutory rate or an officially documented rule. Below the tool we show the formula and the working for your numbers, so you can follow the steps rather than trust a black box. Examples:

• Loans: the standard reducing-balance EMI formula, EMI = P × r × (1 + r)ⁿ ÷ ((1 + r)ⁿ − 1), which is what banks use.
• Indian income tax: the slab rates, ₹75,000 standard deduction, the rebate for taxable income up to ₹12 lakh with marginal relief, surcharge and 4% cess under the Income Tax Act, 2025 for FY 2026-27.
• Small savings schemes: the interest rates notified by the Government of India for the current quarter (for example PPF, SCSS, SSY and POMIS).
• Science, maths and conversions: exact definitions where they exist, such as 1 inch = 2.54 cm and 1 pound = 0.45359237 kg.

2. Where our rates and rules come from

For tax, payroll and savings figures we work from primary sources: the relevant Act and Finance Act, official notifications and circulars, the Income Tax Department, EPFO, India Post and the Reserve Bank of India, and for other countries the equivalent official bodies such as HMRC (UK) and Revenue (Ireland). Pages that depend on these figures list their sources and the date they were last checked.

3. How we test each calculator

Before a calculator goes live, and again whenever we change it, we run it against worked examples whose answers we have calculated independently, including edge cases such as zero values, very large numbers and the boundaries between tax slabs. Results are compared with official examples or calculators wherever they are published.

4. How we keep pages up to date

• Budget and law changes: tax and payroll calculators are reviewed after every Union Budget and whenever a rule changes mid-year, for example the move to the Income Tax Act, 2025 from 1 April 2026.
• Quarterly rates: small savings scheme rates are checked each quarter when the government announces them.
• Regular review: pages are re-checked on a rolling basis, and each reviewed page shows its "Last reviewed" date so you can see how recent the check is. Tax and savings pages also list their sources.

5. What our calculators do not do

Our results are estimates for education and planning. Some calculators use simplifying assumptions, such as a flat expected return or average tax rates for other countries, and we say so on the page. They cannot take every personal detail into account, so they are not tax, legal, medical or investment advice. For decisions that matter, please speak to a qualified professional. See our disclaimer.

6. Your data

Calculations run in your browser. The numbers you enter are not sent to or stored on our servers. Our privacy policy explains the analytics and advertising cookies the site uses.

7. Who is responsible

YogiCalc is built and maintained in India by the YogiCalc team, led by founder Paresh Pavani of YoGi Dynamic Solutions LLP, Mumbai. Corrections are reviewed by the team before a page is updated.

8. Found a mistake?

Please tell us. Email calc@yogicalc.com with the calculator name, the numbers you entered and what you expected. We aim to reply within two to three working days, and we correct confirmed errors as quickly as we can.

Last updated: 5 November 2026