Free online tool
Percentage Calculator
Work out a percentage, compare two numbers or find an increase or decrease. Enter your numbers below to see the answer and the steps.
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What is X% of a number?
Enter a percentage and an amount. The answer updates as you type.
Result
Example answer
Result
30
15% of 200 is 30.
Choose how many decimal places to show.
How we worked it out
15 ÷ 100 × 200 = 30
Need percentage difference or points? Compare amounts or rates
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Percentage formulas
Not sure which formula to use? Start with what you want to find.
Find a percentage of an amount
Result = (Percentage ÷ 100) × Number
Example
A 15% discount on 200 saves you 30. Subtract 30 from 200 to get a final price of 170.
(15 ÷ 100) × 200 = 30
Find what percentage one number is of another
Result = (Part ÷ Total) × 100
Example
If 30 out of 200 people say yes, that is 15% of the group.
(30 ÷ 200) × 100 = 15%
Find how much a number has increased
Increase = (New − Original) ÷ Original × 100
Example
Going from 80 to 100 is an increase of 20. Compare that 20 with the starting value of 80.
(100 − 80) ÷ 80 × 100 = 25%
Find how much a number has decreased
Decrease = (Original − New) ÷ Original × 100
Example
A price falling from 100 to 80 has dropped by 20, or 20% of its original price.
(100 − 80) ÷ 100 × 100 = 20%
Find the percentage difference between two values
Difference = |A − B| ÷ ((A + B) ÷ 2) × 100
Example
For 80 and 100, the gap is 20 and the average is 90. Divide the gap by that average.
20 ÷ 90 × 100 ≈ 22.22%
Find the change in percentage points
Point change = New rate − Original rate
Example
A rate going from 20% to 25% rises by 5 percentage points. Its relative increase is 25%.
25% − 20% = 5 percentage points
For percentage change, start with a value above zero. For percentage difference, use zero or positive values. See how the calculations work →
What is a percentage?
A percentage tells you how much there is out of 100. So 25% means 25 out of 100, which is the same as one quarter.
You use percentages when checking a sale price, turning marks into a score or comparing this month's sales with last month's. The question tells you which formula to use.
Get the formula cheat sheet →
A few common questions
Questions about percentages
These are easy mistakes to make, even when the arithmetic is right.
How do I calculate a percentage of a number?
Divide the percentage by 100, then multiply by the number. For 15% of 200, that is 15 ÷ 100 × 200 = 30. If you are working out a discount, 30 is the saving, so the price after the discount is 170.
Can a percentage be more than 100%?
Yes. It means the amount you are comparing is larger than the amount you started with. For example, 300 is 150% of 200 because 300 ÷ 200 × 100 = 150.
Why does adding 20% and then taking off 20% not give the original amount?
Because the second percentage uses a different amount. Add 20% to 100 and you get 120. Taking 20% off 120 removes 24, leaving 96. The rates match, but the amounts they apply to do not.
What is the difference between percentage change and percentage difference?
Use percentage change when you have a starting value, such as an old price and a new price. It compares the change with the starting value. Percentage difference compares two values using their average, so neither one is treated as the starting point. For 80 and 100, the increase from 80 is 25%, while the percentage difference is about 22.22%.
Why can I not calculate a percentage change from zero?
The formula divides the change by the starting value. Dividing by zero does not give a defined percentage. If an amount goes from 0 to 50, you can say it rose by 50, but this formula cannot express that rise as a percentage.
Can I use negative numbers?
You can use negative numbers when finding a percentage of an amount or expressing one number as a percentage of another. For percentage change, this calculator needs a starting value above zero. For percentage difference, both values must be zero or positive. If both are zero, the tool reports a 0% difference.
Does the decimal setting change the calculation?
No. It only changes how many decimal places you see in the answer. The calculator uses the numbers you entered. Like other tools that use browser number arithmetic, it can lose precision with very large numbers or very small differences. Check the calculation limits if you need exact decimal arithmetic.
Do I need an account, and what happens to my numbers?
You do not need an account or a file upload. The calculator works in your browser and does not keep a calculation history. Copy answer puts the result on your clipboard. Share calculation creates a link containing your numbers, so anyone you send that link to can see them.
A quick check before you use your answer
Make sure you have chosen the right calculation and entered the right starting amount. You can open the steps to check the formula or change the decimal setting for a more detailed answer. If something looks wrong, tell us what you entered and what you expected.
Read about rounding and calculation limits →