justyourcalculatorPercentage Calculator
Every everyday percentage question, with the working shown.
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Percentage Calculator
Percent of, percent change and more
Fill in any two boxes; the empty one is solved.
20% of 150
30
How it was calculated
- Y = P / 100 × X
- Y = 20 / 100 × 150 = 0.2 × 150
- Y = 30
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How the percentage calculator works
A percentage is a number out of 100, so P% means P / 100. To find P% of X, multiply X by P / 100. To find what percent Y is of X, divide Y by X and multiply by 100. To find the whole when you know a part and its percent, divide the part by P / 100.
Percent change compares a new value with an old one: (new - old) / old × 100. A positive result is an increase and a negative one is a decrease. Percent difference compares two values with their average and has no direction, so the order doesn't matter.
Increasing a number by P% multiplies it by (1 + P / 100); decreasing it multiplies by (1 - P / 100). That's why a 10% rise followed by a 10% fall leaves you 1% lower, not back where you started.
Using and checking your result
Published by JustYourCalculator. Check the units and assumptions above, and compare a known example before relying on the output. Calculations use browser arithmetic and may round displayed values.
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