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6 guides

Guides on the numbers behind your decisions.

How loan EMIs, investments, BMI, and AI API costs are actually calculated — and where the shortcuts and formulas fall short.

Web Development

WHMCS Module Development: A Practical Guide for Hosting Businesses

What WHMCS modules actually do, the three types you'll encounter, and how to decide between an existing module and a custom-built one.

September 8, 2026 · 6 min read

AI

AI API Pricing Explained: How Token-Based Costs Actually Work

Why AI APIs bill in tokens instead of requests, why output costs more than input, and practical ways to estimate and reduce your spend.

September 1, 2026 · 6 min read

Health

Understanding BMI: What It Measures and Where It Falls Short

BMI is a 200-year-old formula still used as a first-pass health screen today. Here's what it actually calculates, and the specific situations where it misleads.

August 25, 2026 · 5 min read

Finance

Fixed Deposit vs Recurring Deposit: How to Choose

FD and RD both pay guaranteed interest, but they solve different problems. Here's how the compounding, liquidity, and tax treatment differ.

August 18, 2026 · 4 min read

Finance

SIP vs Lump Sum: Which Investment Strategy Actually Wins?

The math behind SIP and lump-sum investing, when each one wins historically, and how to decide which fits your situation.

August 11, 2026 · 6 min read

Finance

How EMI Is Calculated: The Complete Formula Explained

The exact formula banks use to calculate your loan EMI, a worked example, and how principal, rate, and tenure each move your monthly payment.

August 4, 2026 · 5 min read