CALCULATORS
Percentage Calculator
Calculate percentage change, percentages of values, ratios, increases and decreases from one flexible calculator.
Quick answer: Choose the calculation you need, enter both values and review the result instantly.
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How to use Percentage Calculator
- Choose the questionPick what you need: X% of Y, what percent X is of Y, or percentage change.
- Enter the numbersType both values. Results update instantly.
- Check the baselineConfirm which number is the starting value, because percentage change depends on direction.
About this tool
Percentages come up in discounts, taxes, grades and price changes, and it is easy to start from the wrong number. Choose the kind of question first, then enter the values.
Common uses: Work out a percentage of a number, percentage change, discounts, markups, increases and decreases for everyday decisions.
Practical example: For a price change, use the percentage-change mode and enter the old value followed by the new value to see the increase or decrease.
Important limitation: A percentage result depends on the direction and baseline you choose. Confirm whether the question asks for a percentage of, or a percentage change from, a value.
All calculations run in your browser. Read the privacy information.
How it works
It applies the basic percentage formulas (part ÷ whole × 100, and change ÷ original × 100) for the question type you choose.
Real-world uses
- Working out a discount price
- Calculating a raise or price increase
- Finding what percent of a goal is complete
Choosing the right percentage question
Percentage change from A to B tells you how much a value rose or fell compared with where it started: (B − A) ÷ A × 100. A price that goes from 80 to 100 rose by 25 percent, but going back from 100 to 80 is a 20 percent drop, because the starting point differs. Always identify the baseline.
“What is A percent of B” is the discount or tax question: 15 percent of 240 is 36. Adding or subtracting a percentage works directly on the price: subtract 20 percent from 50 to get 40, or add 8 percent sales tax to see the total. “A is what percent of B” converts a score or share, such as 42 out of 60 being 70 percent.
Percent and percentage points are different. A rate moving from 10 percent to 12 percent is a rise of 2 percentage points, which is a 20 percent relative increase.
Tips for better results
- Percentage change = (new − old) ÷ old × 100.
- A 50% increase followed by a 50% decrease does not return to the start (it ends 25% lower).
- To add a percentage, multiply by 1 + p; to subtract, multiply by 1 − p.
Frequently asked questions
How do I calculate percentage increase?
Enter the original and new values in the percentage-change workflow; the result uses the original value as the baseline.
Can I calculate a discount?
Yes. Use the percentage-of or decrease workflow with the original price and discount percentage.
Are my calculations uploaded?
All calculations run in your browser.
What is the difference between percent and percentage points?
Going from 10% to 12% is a 2 percentage-point rise, which is a 20% relative increase.
How do I calculate a discount?
Use Subtract A% from B: enter the discount percentage and the original price. The result is the sale price.
Why is a 50 percent rise followed by a 50 percent fall not back to the start?
The fall is applied to a larger number. 100 up 50 percent is 150; down 50 percent is 75, which is 25 percent below the start.
How do I find what percent one number is of another?
Choose A is what percent of B, enter both numbers, and read the result. It is A divided by B times 100.