Calculators
Percentage Calculator
Calculate percentages, ratios, and percent change.
Core percentage questions
Increase / decrease a value
Enter values to calculate percentages.
How to use
- Enter the two values involved in your percentage question.
- Review results for “X% of Y”, “X is what % of Y”, and percent change.
- Optionally apply an increase or decrease percentage to a base value.
About this tool
Percentage problems show up in discounts, growth metrics, grades, and tip calculations. ToolForge computes the common variants in one place.
Percent change uses ((new − old) / |old|) × 100. Division by zero yields an unavailable result rather than crashing.
Examples
15% of 200
Result: 30
FAQ
How is percent change defined?
((new value − original value) / absolute value of original) × 100. If the original is zero, percent change is undefined.
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