Free Percentage Calculator
Three calculators in one: find a percentage of a number, find what percent one number is of another, and calculate percentage increase or decrease — with the formula shown.
How to use
- Pick the calculation type: “X% of Y”, “X is what % of Y”, or “% change”.
- Enter the two numbers and click Calculate.
- See the answer with the full formula so you can verify it.
Frequently asked questions
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 20% of 150 = (20 ÷ 100) × 150 = 30.
How do I find the percentage increase between two numbers?
Subtract the old value from the new value, divide by the old value and multiply by 100: ((New − Old) ÷ Old) × 100.
What is the difference between percent and percentage points?
A move from 10% to 15% is a 5 percentage-point rise, but a 50% relative increase. Our calculator shows the relative change.
Is my data sent anywhere?
No — every calculation runs in your browser. Nothing is uploaded or stored.
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