What is Percentage Formula ?

We use percentages frequently in our daily lives. For example, we may need to calculate percentages to understand the benefits we’ll receive after discounts, marks scored in exams, interest rates of banks, and much more. It is important to understand how we can calculate percentages quicker and faster. That’s when percentage formulas come into the picture. 

What is a Percentage Formula? 

In mathematics, percentage means “out of 100”. It is a number that can be denoted as a fraction out of 100%. For example, 25% can be denoted as 25/100. 

Surprisingly, the percentage can also be expressed in a decimal form. For example, 0.50%

To calculate a percentage, we can simply use the percentage formula. The percentage formula is expressed as:

Percentage Formula = (Value / Total Value) X 100

In other words, a percentage formula is when we divide a part of the total number by the whole value and multiply it by a hundred. For example, (5/10)X100 = 0.5 X 100 = 50%

How to Calculate Percentage of a Number?

If you want to calculate the percentage of a particular number such as 10% of 50, you can use the formula:

(P/100) X Number = X


  • (P/100) is the percentage given in the question 
  • x is the resultant answer

For example, calculate 20% of 60. Therefore, 

(20/100) X 60 = x

0.20 X 60 = x

12 = X

We can say, 20% of 60 is 12. 

How to Calculate Percentage Change?

In mathematics, there are two kinds of percentage change. 

The first type of percentage change is in percentage increase. Percentage increase refers to the amount of increase that has occurred in a value over a period of time. This can be calculated using the formula: 

Percentage Increase = [(Final Value – Initial Value) / Initial Value] X 100

In the above formula, the final value refers to the value after the increase, and the initial value refers to the value before the increase. 

The second type of percentage change is a percentage decrease. Percentage decrease, on the other hand, is the opposite of percentage increase. It refers to the amount by which a value has been decreased over a period of time. This can be calculated using the formula:

Percentage Decrease = [(Initial Value – Final Value) / Initial Value] X 100

In the above formula, the initial value is the value before the change has occurred, and the final value is the value after the value has decreased over a period of time. 

How to Calculate Percentage Difference?

Percentage Difference is a percentage formula that can be used to compare the percentages of two different terms. The percentage difference formula can be expressed as the difference between the values divided by the average of the values and multiplied by a hundred. The formula is 

Percentage Difference = {(Value 1 – Value 2) / ([Value 1 + Value 2] / 2)} X 100

For example, you want to calculate the percentage difference between the cost of a product ABC this year and last year. This year the product cost Rs. 100 and last year it cost Rs. 50. 

We will simply put the values in the formula, {(100 – 50) / ([100 + 50] / 2) x 100

= (50 / 75) X 100 = 66.66%

In simpler words, this shows that the cost of the product ABC is 66.66% more than that of last year. 

Learn Mathematics from Cuemath

However, mathematics as a subject is not preferred by most students. It’s a subject all about numbers and formulas which can become monotonous at times. However, this occurs due to a lack of knowledge about the basics. If you’re looking for online math classes that are highly engaging and that ignite the fire inside you to learn mathematics, then Cuemath is the right choice for you. Cuemath not only provides highly engaging lectures but also provides puzzles and worksheets that keep you engaged.