Calculate a percentage of a value, percentage change, or a value from a percentage.
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About Percentage Calculator
Three calculators in one: what is X% of Y, X is what percent of Y, and the percentage change from X to Y. Each result shows the formula used and can be copied, and the percentage change also shows the absolute difference and whether it is an increase or decrease.
Common uses
- Work out a discount, tip or tax amount
- Calculate what share of a total a value represents
- Measure the percentage increase or decrease between two metrics
- Compare before and after numbers in a performance report
FAQ
- How do I calculate a percentage of a number?
- Divide the percentage by 100 and multiply by the number. For example, 15% of 240 is 0.15 x 240 = 36.
- How do I calculate percentage change?
- Subtract the old value from the new value, divide by the absolute old value and multiply by 100. Going from 80 to 100 is (100 - 80) / 80 x 100 = 25% increase.
- Why is a 50% decrease not undone by a 50% increase?
- Each percentage applies to a different base. 100 minus 50% is 50, and 50 plus 50% is only 75; returning to 100 requires a 100% increase.
- Can you calculate a percentage change from zero?
- No. Percentage change divides by the starting value, so a change from 0 is undefined.