With the **Percentage calculator** it is very simple to calculate the percentage giving the initial figure and the percentage that you want to apply to it.

## How to use the percentage calculator

It's very simple. Just enter the initial value, and then indicate in number, the percentage to apply. and then click "Calculate! The website will give you three values:

- The percentage value of that number. As Example, 21% of 100 is 21..
- The value added to the initial value i.e. 21% of 100 is 21%, so if you add 21% to 100, you will give us 121.
- The value subtracted from the initial value, that is, the value to which, if you add 21%, it gives you 100./li>

## Do you know what the percentage is?

A percentage is a mathematical formula, which gives us the proportion in quantity, of a fraction in 100 parts. This may sound somewhat odd, but it is quite simple.

What a percentage does is to indicate a ratio of increase or decrease of a value based on an example of 100 units. So, we can say that if out of 100 units, for example, we want 20, if we have 200, it will be 2 times 100, that is, 20 by 2 which is 40.

To indicate a percentage, the symbol "%" is used wordwide.

## What's the percentage? - How do you find the percentage of something?

**Percentage is one of the many ways of expressing a dimensionless proportion of two numbers**. It is very popular because it can describe situations that involve large numbers (e.g., estimating the chances of winning the lottery), average (e.g., determining the final grade for your course) as well as very small (e.g., the volume proportion of NOβ in the air, also frequently expressed by PPM - parts per million).
One percent is a hundredth. As a percentage sign, we usually use %, but sometimes it is denoted by pct . This means that 5 percents is the same as 5%, 5 pct, 0.05, 5/100 or five hundredths. It is as simple as that, and this percentage calculator is a tool dedicated to working with decimal fractions and percentages. If you are looking for more complicated problems, try to figure out how to calculate the percentage of a percentage.
All this is fine,

**but normally we don't use percentages alone**. Above all, we want to answer, how big is a number in relation to another number? To try to visualize it, imagine that we have something everyone likes, for example, a big pack of cookies (or doughnuts or chocolates, whichever you prefer π, we will limit ourselves to cookies). Let's try to find an answer to the question of what is 40% of 20? That's 40 hundredths of 20, so if we divided 20 cookies into 100 equal parts (good luck with that!), 40 of those parts would be 40% of 20 cookies. Let's do the calculations: 40/100 * 20 = 8. A useful little tip: to divide by 100, simply move the dot two spaces to the left. In our calculation, 40/100 * 20 could be done as (40 * 20) / 100 (it's the same). 40 * 20 is 800. When you move the point in 800 by two digits to the left, you get 8.00, and when you remove all the unnecessary zeros, you get 8. At

**our percentage calculator **, enter 40 and 20 (so it says "40% of 20" is 8).

## Why you need a percentage calculator

**A percentage calculator can be useful on many occasions in daily life **. Such a calculator program can be used to provide assistance with daily functions. Take the example of a trip to the store where you are trying to maximize special discounts or coupons. Using your head to perform certain calculations can be a challenge, if not inaccurate.

**A percentage calculator is created specifically to help a person in cases like these**.
An additional illustration of the benefits of this calculator is that you may have gone out to lunch and the waiter treats you wonderfully; you can use the percentage calculator to find the right tip for him or her. You can determine the amount of money you have spent on your meal and then use the calculator to calculate the correct percentage of that total to arrive at the tip amount. You can even do this when the pizza delivery guy leaves your big pepperoni on your doorstep!
This utility can also be valuable in a financial environment whenever there is a need to calculate data in percentages. Doing so can give you a useful perspective on various scenarios, such as understanding the amount of profit or loss in a business. This is often useful in cases where the numbers involved are significant and the need to display them in simpler terms makes them easier to understand.
To be able to use this calculator, you will want to have a fundamental knowledge of the whole concept of percentage and its importance. Using this percentage calculator when you are online can greatly help you make quick calculations that will allow you to make important decisions. You may be shopping online and be presented with figures to keep in mind. The calculator can be very useful.
Take another example of a scenario where you are about to buy an item in an online store. You should have the item delivered to your residence. You may be in a situation where the cost of delivery is determined by the total cost of the item, meaning that the cost of shipping the product is a percentage of the cost of the product. Using a percentage calculator can help you understand whether or not that cost is reasonable and, as a result, help you make an informed and wise decision about a purchase.
The calculator can be quite advantageous if you end up trying to understand certain economic ramifications as well. If you are online and analyze financial information or reports, you can further simplify all the data by using percentages. You can discover many percentage calculators on the web and use them for free.
A percentage calculator may be particularly useful in many different ways. Calculations can be quite simple or quite complicated. The idea behind this type of application is to make sense of numerical data and encourage the user to make important decisions in various situations.

## Percentage history - percentage sign

Although ancient Romans used Roman numerals I , V , X , L , etc., calculations were often made in fractions that were divided by 100. It was equivalent to the calculation percentages we know today. Calculations with a denominator of 100 became more standard after the introduction of the decimal system. Many of the medieval arithmetic texts applied this method to describe finances, for example, interest rates. However, the percentage of sign% that we know today only became popular recently, in the twentieth century, after years of constant evolution.
The term percentage is usually attributed to the latin percent, that is to say, percent. Actually, it's wrong. We get the term Italian per cent - per cent. The percentage of sign% evolved by the gradual contraction of those words over centuries. Finally, the cento has taken the form of two circles separated by a horizontal line, from which the modern symbol% is derived. The history of mathematical symbols is sometimes astounding. We recommend that you take a look at the origin of the square root symbol!
Recently, the percentage symbol is widely used in programming languages as an operator. It usually means the module operation. On the other hand, in experimental physics, the symbol % has a special meaning. It is used to express the relative error between the true value and the observed value found in a measurement.
Have you ever known a percentage symbol that had an additional circle? That's not a mistake! There are two related signs:

- β° - per thousand - per thousand,
- β± - per thousands - per ten thousand (also known as base point),

Later in the text, we explain in more detail what is meant by millennium, what is a base point and how to convert by milestones and base points to percentages.
Higher proportions use another note (called parts per note), for example, parts per million (PPM), which is often used to measure the concentration of a substance in solution or mixture.

## How are percentages used?

- Discounts in stores: 25 percent discount.
- The sales tax is usually a percentage of the purchase price: 8% of the sales tax.
- Interest rates on savings accounts are generally shown as an annual percentage rate (April): 1.5% April.
- Interest rates charged by credit card companies and mortgage companies are shown as an annual percentage rate.
- Changes in interest rates: interest rates rose one percentage point from 4.5% to 5.5%
.
- Statistics: the margin of error is plus or minus four percentage points
- Credit card rewards: 2% cash back for certain purchases
- News: Approval rates, employment rate and surveys can be expressed using percentages
.
- Portable computers, tablets, and cell phones generally have a battery charge percentage indicator
.
- Weather forecast: 20 percent probability of rain
- Probability: the chance of winning a prize is 1 in 10 or 10 percent
- Humidity: the humidity level is 65%.