Percentage Calculator

To calculate a percentage of a number, select the "Standard" tab in our calculator, enter the value in the "Value" field and the percentage in the "Percentage" field, then click "Calculate." The calculator will show you what the specified percentage of your value is. For example, to find 15% of 200, enter 200 as the value and 15 as the percentage. The formula used is (Percentage ÷ 100) × Value, which in this case would be (15 ÷ 100) × 200 = 30.

Percentage difference and percentage change are two different calculations used in different contexts. Percentage difference compares two values without considering which came first, making it ideal for comparing similar items. It's calculated as the absolute difference divided by the average of the two values. Percentage change, on the other hand, shows how a value has increased or decreased from an original value over time. It's calculated as (New Value - Original Value) ÷ Original Value × 100. Our calculator includes both modes with clear explanations of which to use depending on your needs.

To find what percentage one number is of another, use the "Standard" calculator tab. Enter the first number (the part) as the "Value" and the second number (the total) as the "Percentage." The calculator will show you what percentage the first number is of the second. For example, if you want to know what percentage 25 is of 100, enter 25 as the value and 100 as the percentage. The formula used is (Value ÷ Total) × 100, which gives you (25 ÷ 100) × 100 = 25%. Our calculator automatically provides this calculation along with a clear explanation.

Yes, our calculator includes a specific "Percentage Change" tab designed for calculating increases and decreases. Enter the original value and the new value, then click "Calculate Change." The calculator will show you both the percentage change and whether it's an increase or decrease. For example, if a price changed from $80 to $100, enter 80 as the original value and 100 as the new value. The result will show a 25% increase. The calculator color-codes the results (green for increases, red for decreases) and provides the formula used: (New Value - Original Value) ÷ |Original Value| × 100.

Our percentage calculator performs exact calculations but displays results rounded to two decimal places for readability. This level of precision is sufficient for most everyday uses while keeping the results easy to understand. The underlying calculations are performed with full floating-point precision before rounding for display. If you need greater precision for specialized applications, the formulas are provided so you can perform the calculations manually with as many decimal places as required. For financial calculations in particular, the two decimal places align with standard currency representation.

Common mistakes include confusing percentage points with percentages (e.g., an increase from 10% to 15% is a 5 percentage point increase, not a 5% increase), forgetting to convert percentages to decimals before calculations, and mixing up the order of values in percentage change calculations. Always double-check your inputs and ensure you're using the correct formula for your specific calculation type. Our calculator helps prevent these errors by clearly labeling each input field and showing the formula used.