Guides and Articles
Plain-English guides that explain the money, health and measurement questions behind our calculators. Each guide includes formulas and worked examples.
What Is GST? A Plain-English Guide to India's Goods and Services TaxWhat GST is, how CGST, SGST and IGST work, the current rate slabs and what it means for the price you pay.How to Calculate GST: Adding and Removing GST With ExamplesStep-by-step formulas to add GST to a price or remove it from a GST-inclusive price, with worked examples and common mistakes.How Is EMI Calculated? The Formula Explained With an ExampleThe EMI formula in plain words, a full worked example, and what happens to interest and principal over the life of a loan.How to Reduce Your EMI and Save Interest on a LoanPractical ways to lower your EMI or your total interest: prepayment, tenure, rate negotiation and balance transfer, with real numbers.How to Calculate Percentage: 6 Everyday Methods With ExamplesFind a percentage of a number, percentage change, discounts and reverse percentages with simple formulas and worked examples.Profit Margin vs Markup: What Is the Difference?Margin and markup are not the same thing. Learn both formulas, how to convert between them and how to price a product.What Does Your BMI Mean? Categories, Limits and What to Do NextHow BMI is calculated, what the categories mean, the lower cut-offs often used for Indians, and where BMI falls short.How to Calculate Your Exact Age in Years, Months and DaysA simple method to work out exact age from a date of birth, including borrowing days, leap years and 29 February birthdays.Land Area Units in India: Guntha, Acre, Hectare and Square Feet ExplainedHow guntha, acre, hectare, bigha, cent and square feet relate to each other, with conversion examples for land buyers and farmers.Unit Conversion Cheat Sheet: Length, Weight, Temperature and MoreThe conversion factors you actually need: length, weight, volume, temperature and speed, with exact values and quick tricks.Mean, Median and Mode: Which Average Should You Use?What mean, median and mode tell you, how to calculate each with an example, and why standard deviation matters too.How QR Codes Work and How to Create One That Scans Every TimeWhat is inside a QR code, how error correction works, static versus dynamic codes, and tips for safe, reliable QR codes.HEX, RGB and HSL Colour Codes Explained for BeginnersWhat HEX, RGB and HSL colour codes mean, how to convert between them, and how to pick colours with enough contrast.Image Resolution, Pixels and Megapixels: What the Numbers MeanHow to read image dimensions, megapixels and DPI, what size you need for web and print, and how to keep file size small.