Calculator Guides

Guides & How-To Articles

In-depth explanations of the math behind our calculators — so you understand what the numbers mean, not just what they are.

Finance 8 min read

FD Calculator: How Fixed Deposit Interest is Calculated (With Formula & Examples)

Learn how FD interest is calculated with the compound interest formula. Includes worked examples for quarterly, monthly, and annual compounding, plus TDS rules.

Finance 10 min read

PPF Calculator Guide: Returns, Lock-In, and Why It's India's Best Tax-Free Investment

Current PPF rate (7.1%), EEE tax benefit, 15-year lock-in, partial withdrawal rules, and how PPF compares to FD, ELSS, and NPS — with real numbers.

Health 8 min read

Pregnancy Weight Gain: How Much is Normal? IOM Guidelines Explained

IOM 2009 recommended weight gain ranges by BMI category, trimester breakdown, where the weight goes, and risks of gaining too much or too little.

Finance 8 min read

How to Calculate GST in India — A Complete Guide (2025)

Add GST, remove GST from inclusive prices, understand CGST vs SGST vs IGST, and see worked examples for all 5 slabs: 3%, 5%, 12%, 18%, 28%.

Investing 10 min read

SIP vs FD: Which is Better in 2025? A Data-Driven Comparison

Returns, risk, liquidity, and tax compared with real numbers. We settle the SIP vs Fixed Deposit debate for long-term wealth, short-term goals, and everything in between.

Finance 10 min read

How to Calculate Take-Home Salary in India (2025-26)

Full worked example for ₹12 LPA CTC — breaking down gross salary, income tax (new vs old regime), PF deductions, and the exact monthly in-hand you'll receive.

Health 8 min read

How to Calculate BMI: Complete Guide with Formula & Charts

Learn exactly how BMI is calculated, what your number means, its limitations, and what health professionals say about it. Includes worked examples and healthy range charts.

Finance 10 min read

EMI Calculator Guide: Formula, How It Works & Tips to Reduce Interest

Everything you need to know about EMI — the formula, how banks calculate it, how to use an EMI calculator, and 7 proven strategies to reduce your total loan interest.

Finance 9 min read

Compound Interest Explained: How Your Money Grows & the Rule of 72

Understand compound interest from first principles — the formula, daily vs monthly vs annual compounding, the Rule of 72, and real examples showing how time in market beats timing the market.

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