How do I calculate a percentage of a number?
Divide the percent by 100 and multiply by the number. For example, 20% of 150 is 0.20 x 150 = 30.
Calculators
Percentage Calculator
Work out percentages, percent change, and add or take off a percent.
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What is X% of a number?
%
Answer
30
20% of 150 = 20 / 100 x 150
X is what percent of Y?
Answer
25%
30 / 120 x 100
Percentage change (increase or decrease)
Answer
+25%
From 80 to 100 is a rise of 25%. (new - old) / old x 100
Add or take off a percentage
%
Answer
28.75 / 21.25
25 plus 15% is 28.75. 25 minus 15% is 21.25 (handy for tips, tax and discounts).
How it works
1
Pick the question
Choose the calculator that matches what you want to know, like percent of a number or percent change.
2
Type your numbers
Enter the two numbers. The answer updates as you type.
3
Read the answer
The result shows with the formula underneath, so you can check the working.
Percentage Calculator features
- What is X% of Y, for tips, tax and discounts.
- X is what percent of Y, for scores and shares.
- Percentage increase or decrease between two values.
- Add or take off a percentage in one step.
- Formula shown with every answer.
- Instant results, no signup.
Percentage Calculator FAQ
How do I work out percentage change?
Subtract the old value from the new value, divide by the old value and multiply by 100. From 80 to 100 is (100 - 80) / 80 x 100 = 25% increase.
How do I find what percent one number is of another?
Divide the part by the total and multiply by 100. 30 out of 120 is 30 / 120 x 100 = 25%.
How do I take 15% off a price?
Multiply the price by 0.85. Use Add or take off a percentage above, and it shows both the price plus and minus the percent.
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