Free Online Percentage Calculator
Calculate percentages, increases and decreases quickly and easily.
What is a percentage of a number?
Calculate X% of Y.
What percentage is one number of another?
Calculate what percentage X is of Y.
Percentage increase or decrease
Calculate the percentage change between two numbers.
How it works
- Pick the type of percentage question you have.
- Enter the two numbers in that calculator.
- Read the answer instantly, along with the formula used.
Frequently asked questions
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 20% of 150 is 150 × 20 / 100 = 30.
How do I work out percentage increase or decrease?
Subtract the original value from the new value, divide by the original value and multiply by 100. Going from 80 to 100 is (100 − 80) / 80 × 100 = a 25% increase.
Why is a 50% increase followed by a 50% decrease not the same number?
Each percentage applies to a different base. 100 increased by 50% is 150, but 50% of 150 is 75, so you end at 75. Percentage changes are not symmetric.
What is the difference between percent and percentage points?
If an interest rate rises from 4% to 5%, it increased by 1 percentage point but by 25 percent. Use percentage points when comparing two percentages directly.
Percentage Calculator
Percentages are used everywhere — from calculating discounts and taxes to comparing prices, understanding statistics and working out changes in values. This percentage calculator provides quick answers to some of the most common percentage calculations.
How to calculate a percentage
To calculate a percentage of a number, multiply the number by the percentage and divide by 100.
For example, to calculate 20% of 150:
150 × 20 ÷ 100 = 30
How to calculate what percentage one number is of another
Divide the first number by the second number and multiply the result by 100.
For example, if you want to know what percentage 25 is of 100:
25 ÷ 100 × 100 = 25%
How to calculate percentage increase or decrease
Subtract the original value from the new value, divide the result by the original value, and multiply by 100.
For example, if a price increases from 100 to 125:
(125 − 100) ÷ 100 × 100 = 25%
Common uses for percentages
- Calculating discounts and sale prices
- Calculating taxes and tips
- Comparing changes in prices
- Calculating exam and test scores
- Understanding statistics and proportions
- Calculating increases and decreases
Is this calculator free?
Yes. The percentage calculator is completely free to use and does not require an account or registration.