Calculate percentages, percentage change, and percentage of a number.
Three Ways to Calculate Percentages
Our percentage calculator offers three powerful modes: Mode 1 (X% of Y) answers questions like "What is 20% of 150?", Mode 2 (X is what % of Y) solves "40 is what percent of 200?", and Mode 3 (% Change) calculates growth or reduction between two values.
How to Calculate Percentage Manually
To find X% of Y: multiply Y by X then divide by 100. Example: 15% of 80 = (80 × 15) ÷ 100 = 12. To find what percent X is of Y: divide X by Y then multiply by 100. For percentage change: ((New − Old) ÷ |Old|) × 100.
Common Everyday Percentage Uses
Percentage calculations are essential in finance (interest rates, discounts, tips), academic test scoring, business profit margins, and health metrics.
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