Calculators
Percentage Calculator: Percent of a Number, Percent Change
Work out X% of a number, what percent one number is of another, and the percentage increase or decrease between two values, all on one page. Answers update as you type.
What is X% of Y?
What is% of?
Answer: 30
X is what percent of Y?
is what % of?
Answer: 15%
Percentage change (increase or decrease)
Fromto
An increase of 25% (+20)
How to use the Percentage Calculator
- Pick the question that matches yours: X% of Y, X is what percent of Y, or the change from X to Y.
- Type your two numbers into that line.
- Read the answer straight away; change a number to see it update.
Frequently asked questions
- How do I calculate a percentage of a number?
- Divide the percentage by 100 and multiply by the number. 15% of 200 is 0.15 × 200 = 30.
- How do I find what percent one number is of another?
- Divide the part by the whole and multiply by 100. 30 out of 200 is 30 ÷ 200 × 100 = 15%.
- How do I calculate percentage increase or decrease?
- Subtract the old value from the new one, divide by the old value and multiply by 100. From 80 to 100 is (100 − 80) ÷ 80 × 100 = a 25% increase.
- Why is a 20% drop not undone by a 20% rise?
- Each percentage is taken from a different starting value. 100 down 20% is 80, and 80 up 20% is only 96. You'd need a 25% rise to get back to 100.
- Can I use decimals and negative numbers?
- Yes. Decimals, negative numbers and grouped numbers like 1,250 all work.
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