Percentage Calculator

Reference

How do percentages work?

A percentage is a number expressed as a fraction of 100. The word comes from the Latin per centum meaning "by the hundred." Percentages are the universal language for expressing proportions — used in finance (interest rates, returns), retail (discounts, tax), statistics (probability, margins of error), health (BMI percentiles, body fat), and virtually every quantitative field.

Three ways to calculate percentages

% of a number: Find what a given percentage of a number is. Formula: Result = (Percent / 100) × Value. Example: 15% of 200 = 30.
X is what % of Y?: Find what percentage one number represents of another. Formula: Percent = (X / Y) × 100. Example: 45 is 75% of 60.
% change: Find the percentage increase or decrease between two values. Formula: Change = ((New − Old) / |Old|) × 100. A positive result is an increase; negative is a decrease. Example: from 80 to 100 = +25% increase.

Common use cases

Shopping discounts: What is 20% off $49.99? Use "% of a number" mode — you save $10.00, paying $39.99. Grade calculations: You scored 42 out of 55 — what percentage is that? Use "X is what % of Y?" — that is 76.4%. Business growth: Revenue grew from $10,000 to $13,500 — use "% change" to find +35% increase. Tips: Calculate a 15% or 20% tip on a restaurant bill. Tax: Add 8.5% sales tax to a price using "% of a number" and add to the original. Profit margins: Find what percentage of revenue is profit.

Privacy

All calculations run 100% in your browser. No data is sent to any server.