Percentage Basics
Master the fundamentals of percentage calculations with step-by-step guides, formulas, and practical examples for everyday use.
What You Will Learn
Percentages express a part of a whole as hundredths. Mastering the three core forms — percent-of, what-percent, and percent-change — covers 90% of everyday calculations, from shopping discounts to data interpretation.
Start with the formula Result = (Percentage ÷ 100) × Number. For example, 20% of 80 is (20 ÷ 100) × 80 = 16. Our calculators show every step so you learn the method, not just the answer.
Common pitfalls include confusing percentage points with percent change, and forgetting to convert back from decimals. Each guide below links to a live calculator where you can practice with your own numbers.
Start With These Tools
Percent Of — The Foundation
Calculate X% of Y with step-by-step breakdowns and mental-math shortcuts.
Use the Percent Of CalculatorWhat Percent — Reverse Lookup
Find what percentage one number is of another, with fraction shortcuts.
Try What Percent50 Common Calculations Directory
Instant answers for the most-searched values (50–1000) with full working.
Browse 50 Common CalculationsIn-Depth Articles
How to Calculate Percentage in 3 Steps (With Formula)
Learn how to calculate percentage with the simple formula, 3 worked examples, mental-math shortcuts, and the mistakes everyone makes. Free calculators included.
10 min read
Read ArticleCommon Questions
What is the fastest way to calculate 10% of any number?
Move the decimal one place left. 10% of 250 is 25.0. Double it for 20%, halve it for 5%.
How do I convert a fraction to a percent?
Divide part by whole, multiply by 100. 32 out of 40 is (32 ÷ 40) × 100 = 80%.
What is the difference between percent and percentage points?
Going from 10% to 15% is +5 percentage points, but a 50% relative increase. Always clarify which you mean.
Last updated: · Reviewed by PercentLab Editorial Team
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