Percentage Calculator

To calculate a percentage of a number, divide the percentage by 100 and multiply by the number. For example, to find 25% of 200: (25/100) × 200 = 50. The basic formula is: (Percentage / 100) × Number = Result. Our calculator performs this calculation instantly when you enter the values.

The percentage change formula is: % change = [(New Value - Original Value) / Original Value] × 100. If the result is positive, it indicates an increase; if negative, it shows a decrease. For example, if a price increases from $100 to $120: [($120 - $100) / $100] × 100 = 20% increase.

For percentage increase: [(New Value - Original Value) / Original Value] × 100. For percentage decrease: [(Original Value - New Value) / Original Value] × 100. The key is to always divide by the original value and multiply by 100. Our calculator automatically determines whether it's an increase or decrease based on your input values.

Common applications include calculating shopping discounts, restaurant tips, sales tax, academic grades, business profit margins, investment returns, and statistical analysis. In everyday life, percentages help with budgeting, comparing prices, tracking fitness goals, and understanding financial statements. Businesses use percentages for revenue analysis, market share calculations, and performance metrics.

To convert percentage to decimal, divide by 100 (or move decimal point two places left). To convert decimal to percentage, multiply by 100 (or move decimal point two places right). For example, 25% = 0.25 as a decimal, and 0.75 = 75% as a percentage. This conversion is essential for mathematical calculations involving percentages.

Yes, percentages can exceed 100% when dealing with increases, comparisons, or ratios where one value is larger than the reference value. This commonly occurs in percentage change calculations, such as when something doubles (100% increase) or triples (200% increase). For example, if sales grow from $100 to $250, that's a 150% increase.

Percentage refers to a proportion of 100, while percentage points measure the arithmetic difference between percentages. For example, if interest rates increase from 2% to 4%, that's a 2 percentage point increase, but a 100% relative increase. Percentage points are used when discussing changes in rates, scores, or other percentage-based measurements.

Online percentage calculators are highly accurate when properly programmed. They use standard mathematical formulas and can handle calculations with precision up to many decimal places. However, results may be rounded for display purposes. Our calculator provides accurate results for all standard percentage calculations including basic percentages, percentage changes, and compound calculations.

Different programming languages handle percentages similarly through basic arithmetic operations. Most languages (JavaScript, Python, Java, C++) require converting percentages to decimals before calculations. Some spreadsheet applications like Excel have built-in percentage formatting, while statistical software like R and MATLAB offer specialized percentage functions for data analysis and statistical calculations.

Compound percentage changes involve multiple successive percentage changes applied to the same base value. The formula is: Final Value = Initial Value × (1 + r₁) × (1 + r₂) × ... × (1 + rₙ), where r represents each percentage change as a decimal. For example, two consecutive 10% increases: $100 × 1.10 × 1.10 = $121, not $120.