How it works
The "Percentage Calculator" is designed for quick percentage problemsolving. Simply choose the appropriate formula, input 2 values, and click "Calculate" to see the result.
You can copy the result after the calculation by pressing the button in the answer field.
For instance, if you want to find out what 20% of 150 is, input the values 20 and 150 into the first formula and press "Calculate". The answer, 30, will be displayed in the field to the right of the button.
Below, you can explore the different calculator options and the formulas they're based on. Each description provides a detailed example with a solution.
What is n percent of a?
x = a ÷ 100 × n

a  initial number

n  percentage amount

x  final number
Task: An adult human's body is composed of 70% water. What is the weight of the water in a person who weighs 76kg?
Solution: Initial number ( a )  76, percentage amount ( n )  70. We will be seeking x.
1) First, we find 1 percent: 76 ÷ 100 = 0.76
2) Now, we get 70 percent: 0.76 × 70 = 53.2
Answer: 53.2kg
You can find the answer this way or use our calculator for a quick and accurate calculation.
What percentage is a of b?
x = a ÷ b × 100

a  part of the whole

b  initial number

x  percentage amount
Task: The factory's annual plan is to produce products worth $16,250. In the first quarter, they produced products worth $5,850. What percentage of the annual plan has the factory achieved in the 1st quarter?
Solution: If a is 5,850 and b is 16,250, we will find x.
1) Determine the ratio of the value of the produced products to the expected value: 5,850 ÷ 16,250 = 0.36
2) Now, convert this fraction into a percentage: 0.36 × 100 = 36
Answer: 36%
This formula helps calculate the percentage relationship between two numbers. You can easily find the answer using our calculator.
If a is n percent, what is the total?
x = a ÷ n × 100

a  initial number

n  percentage amount

x  desired number
Task: At the competition, the school team scored 72 points. How many points can be scored in the competition if the points earned by the team make up 80% of all possible?
Solution: If a is 72 and n is 80, then let's find x.
1) First, we'll find 1%: 72 ÷ 80 = 0.9
2) Now let's find 100% (original number): 0.9 × 100 = 90
Answer: 90 points
Using this formula, you can solve similar problems on your own or simply use our calculator.
How much did a increase to become b?
x = (b  a) ÷ a × 100

a  smaller number

b  larger number

x  percentage amount
Task: An item costs $40, and the price was increased to $44. By how many percent was the price increased?
Solution: If a is 40 and b is 44, then let's find x.
1) Find the difference between the costs: 44  40 = 4
2) Now find the ratio of the difference to the initial cost: 4 ÷ 40 = 0.1
3) Convert this fraction to percentage: 0.1 × 100 = 10
Answer: 10%
If the result has a negative value, it means the number was decreased, not increased.
By what percentage is a greater than b?
x = (a  b) ÷ a × 100

a  larger number

b  smaller number

x  percentage amount
Task: An iron cost $50. After some time, its price was reduced to $44. By how many percent was the price decreased?
Solution: If a is 50 and b is 44, then let's find x.
1) Find the difference between the prices: 50  44 = 6
2) Now find the ratio of the difference to the initial price: 6 ÷ 50 = 0.12
3) Convert this fraction to percentage: 0.12 × 100 = 12
Answer: 12%
If the result has a negative value, it means the number has increased, not decreased.
Increase a by n percent.
x = a × (100 + n) ÷ 100

a  initial number

n  percentage

x  final number
Task: Last year, the store bought 200 Christmas trees for the New Year. This year, the number of trees purchased increased by 120%. How many trees were purchased this year?
Solution: If a is 200 and n is 120, then let's find x.
1) Find the percentage of trees purchased, relative to last year: 100 + 120 = 220
2) Get the multiplier for the original number: 220 ÷ 100 = 2.2
3) Now multiply the result of last year by the multiplier: 200 × 2.2 = 440
Answer: 440 trees
For such calculations, you can simply add the percentage as a fraction to 1, multiply by the original number, and get the same answer: (1 + 1.2) × 200.
Decrease a by n percent.
x = a × (100  n) ÷ 100

a  initial number

n  percentage

x  desired number
Task: Apples lose 84% of their weight when dried. How much dried apples will be obtained from 300 kg of fresh apples?
Solution: If a is 300 and n is 84, then let's find x.
1) First, let's find how much weight remains in percentage: 100  84 = 16
2) Now convert this to a fraction: 16 ÷ 100 = 0.16
3) Get the weight of dried apples: 300 × 0.16 = 48
Answer: 48kg
For such calculations, you can simply subtract the percentage as a fraction from 1, multiply by the original number, and get the same answer: (1  0.84) × 300.
Well, that's it! Now you know that such problems are not as complicated as they seem, and you can make calculations quickly and easily. Tell your friends about Percentage Calculator. It might be useful for them too.