About Percentage Calculator
This percentage calculator handles the five calculations people need most: what is X% of Y, X is what percent of Y, percentage change from one value to another, adding X% to a number and subtracting X% from a number. All five cards are on one page, and each answer updates as you type, so you can compare several cases quickly.
For a clean result, enter plain numbers without the percent sign or currency symbols. For percentage change, put the starting value in the From field and the new value in the To field; a drop shows as a negative number. Everything is calculated in your browser, and nothing you type is sent to a server.
How to use Percentage Calculator
- 01
Pick the calculation you need.
- 02
Enter your two numbers.
- 03
The answer appears instantly.
When to use it
- Work out a 15% service charge or commission on an invoice amount.
- Check how much a price, salary or score has gone up or down in percent.
- Find what percentage of a budget a single expense takes up.
- Add VAT or sales tax to a net price, or remove a percentage from a total.
- Convert exam marks, such as 42 out of 60, into a percentage.
Frequently asked questions
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 15% of 200 is 15 / 100 x 200 = 30. Use the first card, What is X% of Y, and enter 15 and 200.
How do I calculate percentage change?
Subtract the old value from the new value, divide by the old value and multiply by 100. A rise from 50 to 75 is +50%. The tool shows a plus sign for increases and a minus sign for decreases.
How do I find what percent one number is of another?
Divide the first number by the second and multiply by 100. For instance, 30 is 15% of 200. Use the card named X is what percent of Y and enter 30 and 200.
Why is a 50% increase followed by a 50% decrease not back to the start?
Because the second percentage is taken from a larger number. Starting at 100, a 50% rise gives 150, and a 50% fall from 150 gives 75, not 100. Percent change always depends on the starting value.
How do I add or subtract a percentage from a price?
Use the Add X% to Y or Subtract X% from Y card. Adding 20% to 80 multiplies it by 1.20 and gives 96. Subtracting 20% multiplies by 0.80 and gives 64.
Is my data stored or uploaded?
No. The calculation runs in your browser, so the numbers you type stay on your device. There is no sign-up and no limit on how many calculations you can make.