There are things in life that we can’t always understand. One of them is percentage. But don’t worry, we’ve all been there. This article aims to help you understand how to calculate a percentage, without needing a calculator. So, whether you need to calculate the amount of your salary increase, the discount rate on your next purchase or simply because you like numbers, this article is for you.

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## Understanding the percentage formula

Before diving into the subject, it is crucial to understand the concept of percentage. A percentage is simply a way of expressing a fraction or part of 100. For example, if you have 25 euros out of 100 euros, that represents 25%.

To calculate a percentage, the formula is quite simple:

`(Value / Total) * 100 = Percentage`

This formula is the key to calculating percentages. It may seem complicated at first, but once you understand its principle, it will become child’s play.

## Mental calculation method for percentages

Now that you understand the formula, let’s move on to the mental calculation method. This method will allow you to calculate quickly percentages without a calculator.

To do this, simply break down the percentage you want to calculate into easier-to-handle percentages. For example, to calculate 15% of an amount, it is easier to first calculate 10% of that amount, then add another 5% to it.

Another example, to calculate 35%, you can calculate 30% (which is 3 times 10%) and add 5%.

## How to calculate the percentage increase or reduction?

There are many times when you need to calculate a percentage increase or reduction. For example, you may need to know how much the price of a product has increased or decreased.

To do this, the formula is as follows:

`(Final value - Initial value) / Initial value * 100 = Percentage increase or reduction`

This formula will allow you to quickly determine the increase or reduction in percentages.

## How to calculate a percentage without a calculator?

Now, let’s tackle the question of how to calculate a percentage without a calculator. There are several methods for this. One of the simplest methods is to use the basic percentage formula and do the mental math.

For example, if you want to know what percentage 20 euros represent out of a total of 200 euros, you use the formula `(Value / Total) * 100`

. This gives `(20 / 200) * 100 = 10%`

.

You can also use a fraction method. For example, if you want to know what percentage 1/5 represents, you know that 1/5 is equal to 20% because 100 divided by 5 is 20.

In conclusion, calculating a percentage can seem intimidating at first, but once you know the formula and have a little practice, it’s actually quite simple. And the best part is, you don’t even need a calculator for this. So the next time you wonder **“how to calculate a percentage without a calculator”**, remember this article and the methods you learned there. You will be able to calculate percentages with confidence and speed. So, it’s your turn now!

### Become a percentage master

Now that you have all the keys to becoming a percentage master, don’t hesitate to put your new skills into practice. Whether to quickly calculate it in your head, to evaluate a price increase or reduction, or even to apply it to your salary, the percentage will now have no more secrets for you. So, don’t give up when faced with numbers, and remember: calculation is also a question of training and habit.