Learn the maths behind every calculator
Long-form explainers on BMI, mortgages, compound interest, percentages, calories, and unit conversions. Written to help you get the right answer, not just a number.
How to Calculate Your BMI Accurately (With Worked Examples)
The full BMI formula explained, worked examples in both metric and imperial units, the official healthy ranges, and what BMI actually misses.
Understanding Compound Interest: A Complete Guide
The compound interest formula demystified — with clear examples showing how starting early, compounding frequency, and regular contributions change outcomes.
Mortgage Calculator Explained: Principal, Interest, Taxes & Insurance
Every part of a monthly mortgage payment — PITI, PMI, HOA, and the amortisation schedule — decoded with real numbers and a step-by-step worked example.
Percentage Calculations Made Simple
Every percentage problem solved by one of three formulas. Learn them once, add a couple of mental-math shortcuts, and you will never be stumped by a discount tag again.
How to Calculate Calories and Macros for Weight Loss
BMR, TDEE, calorie deficits, and protein/carb/fat splits explained with real numbers — plus the three most common mistakes that stall fat loss.
Unit Conversion Basics: Metric vs Imperial
A practical walkthrough of converting length, weight, temperature, volume, area, and speed — with the exact factors you actually need and a handful of mental shortcuts.
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