How to Calculate — Step-by-Step Guides

Every guide follows the same teacher-style structure: what it is, the formula, a worked example with real numbers, and how it varies by country.

Health & science

⚖️

How to Calculate BMI

BMI formula, metric and imperial examples, and regional thresholds

🧬

Mean, Median, Mode & Standard Deviation

Compare measures of centre and spread with worked examples

Finance

📈

How to Calculate Compound Interest

The compound interest formula, examples and compounding frequency

🏠

How to Calculate Mortgage Payments

Monthly payment formula, amortization and country differences

Core math

How to Calculate Percentages

Percent of a number, change and reverse percentages

Fractions & Decimals

Add, subtract, multiply, divide and convert fractions

🔣

Order of Operations

Work through brackets, powers, multiplication and addition

🔢

Ratios & Proportions

Simplify ratios, solve proportions and scale quantities

Geometry

📐

Area & Perimeter

Calculate shapes with formulas and worked examples

📦

Volume

Find the volume of cubes, cylinders, spheres and cones

International

🧠

Mental Math Tricks

Mental arithmetic methods and when they are useful

🌏

Reading Large Numbers by Country

Millions, billions, lakh, crore, 万 and 億

Cite this page APA · MLA · BibTeX

APA

WorldCalculators.org. (2026, September 23). How to Calculate: Step-by-Step Math Guides with Examples. https://worldcalculators.org/learning/how-to/

MLA

“How to Calculate: Step-by-Step Math Guides with Examples.” WorldCalculators.org, 23 Sept. 2026, worldcalculators.org/learning/how-to/.

BibTeX

@misc{worldcalculators2026learninghowto,
  title        = {How to Calculate: Step-by-Step Math Guides with Examples},
  author       = {{WorldCalculators.org}},
  year         = {2026},
  howpublished = {\url{https://worldcalculators.org/learning/how-to/}}
}

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