Percentage Calculator
Calculate percentages, percentage change and what-percent-of in one place.
X% of Y
% of
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X is what % of Y
of
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% change (X → Y)
→
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How to use Percentage Calculator
- 1Pick the calculation you need from the three sections.
- 2Enter your numbers.
- 3The result updates live as you type.
Why use this tool
- Covers the three most common percentage calculations in one tool.
- Live results, no button needed.
- Handles negative numbers and decimals correctly.
Frequently asked questions
How is percentage change calculated?
Percentage change = ((new value − old value) / old value) × 100. A positive result is an increase, negative is a decrease.
What if the old value is zero in percentage change?
Percentage change is undefined when the starting value is zero, since you can't divide by zero — the tool will show this case as N/A.