With this free **percentage calculator**, you can easily calculate a percentage increase, the percentage of a number, the percentage difference between two numbers, and what percentage of one number is the other number. You can also instantly add a percentage to a number or subtract a percentage from a number. Moreover, you can easily calculate the number before the percentage increases and the number before the percentage decreases.

Quick tip:

Press Tab key to move to the next field. Press Shift + Tab keys to move to the previous field. Press Enter key to calculate the result.

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Find out percentage of a number, percentage increases, decreases, differences, and more

**1%=1/100**- 5% of 300=300/100 * 5=15

Calculating a percentage from a specific number may seem redundant these days. After all, unlimited possibilities, technological advances and apps allow us to calculate quickly whether using a calculator on a smartphone or using the right formulas in Excel. There is also a perfect website that you can save in your favourites, namely the percentage calculator. You can return to the site whenever you need to, and by entering the required data, the percentage calculator will give you the required answers in seconds. However, what about when you can't use the site? It is useful to know the basic mathematical operations which, when needed, will answer the needed question on how to calculate the percentage from a given number.

The quickest way to calculate the percentage of a particular number is by first converting the percentage to a fraction and then multiplying the fraction by the given number. For example, if you need to calculate how much is 5% of the number 70, you go to the following operation:

5% * 70=(5/100) * 70=(35/100)=3.5

The second way to calculate a percentage from a specific number is to use a ratio.

This is an equality of two quotients, which is written as:

(a/b)=(c/d)

To determine an unknown, the most common way is the 'cross' method. Once you have arranged the correct ratio, you can multiply the quantities diagonally and then compare them to each other. For example, if you need to calculate 25% of the number 20 you go to the operation:

- 20: 100% (where the number 20 corresponds to 100%)
- x: 25% (where x is the answer to the question of how much is 25% of 20) Then you multiply the quantities crosswise,
- that is
- 20 * 25%=100% * x

and you go on to the following operation:

x=(20 * 25%) / 100%=5

It is worth remembering that with this method, the number on the diagonal of the unknown x you immediately write in the denominator of the fraction, and the product of the other numbers in the numerator.

To answer the question of what percentage of the first number is the second number, you need to calculate the action of what fraction of the first number is the second number and represent this fraction as a percentage. At first, calculating such an operation may sound complicated, but once you have worked out the values, it is enough to calculate the operation. To answer the question what percentage of the number 12 is the number 3, follow these steps:

(3/12)=(3/12) * 100%=(300%/12)=25%

Percentage increase and decrease are two types that qualify as percentage change, which are used to express the ratio of the comparison between the initial value, and the result of the change in value. In this case, a percentage decrease is a ratio that describes a decrease in the value of something by a certain rate, while a percentage increase is a ratio that describes an increase in the value of something by a certain rate.

The simplest way to determine whether a percentage change represents an increase or decrease is to calculate the difference resulting between the original value and the remaining value to find the change. Then divide the change by the original value and multiply the result by 100, which will give you the result. If the result is a positive number - the change is a percentage increase. However, if you get a negative result then the change is a percentage decrease.

Although describing the calculation of percentage changes sounds like a complicated process, it is not. What's more, the ability to calculate percentage changes is useful on a daily basis, especially in the business world - if you own a store, you can calculate the difference in the number of customers who shop in your store, or visualise how much money you save when you shop at a 20% sale.

Assume that the original price of a bag of tomatoes is 3 PLN and on the next day the price per bag is 1.80 PLN. What is the percentage decrease? Apply the formula below:

percentage decrease=(older - newer) ÷ older

percentage decrease=(3 - 1.80) ÷ 3=0.40=40%

In order to increase a specific number by a percentage, you need to use a percentage to decimal conversion. The easiest way to get this result is to move the decimal point two points to the left. For example, 30% of the decimal is 0.3 and 50% of the decimal is 0.5. With an advanced calculator, you can quickly get the result converted to decimal, but it is worth knowing how to do the operation without any technology.

For example - you want to increase the number 10 by 50%. By converting 50% you get 0.5. Perform multiplication 10 * 0.5=5.

To increase the number 10 by 50% of its value it is enough to add 10 and 5, which gives us 15.

Decreasing a specific number by a percentage is the reverse of the last step of increasing a number by a percentage. The easiest way to get a number to decrease by a percentage will be to use a percentage to decimal conversion - exactly the same as when increasing a number by a percentage.

Knowing that 50% in decimal value is 0.5, and also to increase the number 10 by 50% it is enough to perform multiplication 10 ⋅ 0.5=5, getting the result decreasing 10 by 50% should not be a problem. It is enough to perform the action negatively, i.e. to subtract 5 from 10, which gives us 5.

Performing the operations connected with increasing and decreasing a number by percentage initially looks exactly the same, which certainly makes things easier. Only the last step differs in adding or subtracting the result from the given number, but remembering to add numbers when increasing and subtracting numbers when decreasing should make things even easier.

A percentage calculator is a mathematical tool that helps calculate various percentage values based on specified parameters. It is an incredibly useful tool in many situations, both in everyday life and in business or academia. Below are various situations where we might need a percentage calculator:

**Shopping and Discount Calculations:**When shopping, we often encounter various discounts and promotions. A percentage calculator allows us to quickly calculate the discount value and the final price of the product.**Tax and Tip Calculations:**When dining out or paying bills, a percentage calculator can be helpful in quickly calculating the tip amount or tax that needs to be added to the bill.**Personal Finance Percentages:**Planning a household budget or savings, a percentage calculator helps calculate interest on deposits, loans, or other financial parameters, allowing for better financial management.**Investment Analysis:**In the world of investment finance, a percentage calculator is an invaluable tool. It allows for calculating both the percentage increase in investment value, potential losses, or investment returns.**Loan-related Calculations:**When planning loan repayments, a percentage calculator can be very helpful. It allows for quickly calculating the installment amount, total loan cost, or annual interest rate.**School and Academic Mathematics:**In education, a percentage calculator is often used to explain and solve mathematical problems related to percentages, facilitating understanding of the material and knowledge acquisition.**Business Data Analysis:**In business, especially in the finance department, a percentage calculator is essential for analyzing data related to profits, losses, growth, or decline in stock values, or other financial indicators.**Percentage Calculations in Medicine and Natural Sciences:**In medical and natural sciences, a percentage calculator is useful for calculating various indicators and statistical data, such as the percentage of disease occurrence in the population.**Real Estate Valuation:**A percentage calculator can also be used to calculate the percentage increase or decrease in the value of real estate, which is essential for making decisions regarding real estate investments.**Marketing Planning:**In the field of marketing, a percentage calculator can be used to calculate changes in the reach of advertising campaigns, conversions, click-through rates, or other marketing performance metrics.

In summary, a percentage calculator is an indispensable tool in many areas of life, helping to quickly and accurately calculate various percentage values and analyze data. Its versatile application makes it an essential tool for individuals, businesses, or institutions.