Since the denominator of a fraction can be any natural number, there are fractions whose denominators are decimal values: 10, 100, 1000, 10000. Such fractions are called decimal fractions. Even this is the basic mathematical operations, with our converter, you can easily convert decimals to percents.

You do not need to use a calculator for these conversions. When you try our converter, you will see why we are the best!

Take a look other related calculators, such as:

What are decimals? – an introduction

Decimal fractions written in decimal notation are called decimal numbers. Each decimal number consists of two parts. The first part indicates how many whole units there are, and the second part how many parts of the whole there are. The decimal number does not make a conversion if we write many zeros at will after the last decimal. The decimal number does not change if we omit zeros or more zeros from the last decimal places.

A fraction is written in a decimal number by dividing the numerator by the denominator (we already know that a fraction line means division).

If the first digit we discard when rounding decimal numbers is 0, 1, 2, 3, 4, then the last digit we hold does not make a conversion, and if the first digit we discard is 5, 6, 7, 8, 9, then the last number we have increased by 1.

If we round the number 3.561286 to three decimal places, we get 3.561,
and if we round the same number to four decimal places, we get 3.5613.

The number of integers is separated from the number of parts by integers by a comma (decimal point). You can see that we have the numbers to the right of the decimal point. We called them decimals. In each decimal number (3.5613), all the decimals together make up the number 56, the decimal part for a given decimal number.

What are percents? – an introduction

The percentage is a fraction with the denominator hundred. We can write each percent in the form of a fraction, or a decimal number, by dividing it by a hundred. Also, every decimal number or fraction can be written as a percentage.

The percentage label is %.

Percentages help us every day. For example, if we want to compare different prices of products with different masses, it is enough to convert the masses of these products to the same initial size 100.

For 50g of coffee A, you need to pay $3, and for 75g of coffee B, you need to pay $4.2. Which one is more affordable?

Step 1: Convert coffee A mass to 100g.
Result 1: We need to multiply mass with value 2. Multiply the price with value 2, and you will need to pay $6 for 100g of coffee A.

Step 2: Convert coffee B mass to 100g.
Result 2: We need to multiply mass with value 1.33. Multiply the price with value 1.33, and you will need to pay $5.59.

Conclusion: It is more affordable to buy coffee B.

You can also use our percent calculator to calculate without potential errors quickly.

How to convert decimal to percent by hand?

It is not necessary to use a calculator to obtain accurate values. Calculation by hand is also possible. Since the percentage is a fraction with a denominator of 100, when we convert it to a decimal number, we act as if we divide it by 100. The next step is to move the decimal point two places to the left.

On the other hand, when we convert a decimal number to a percent, we act as if we are multiplying it by 100. The next step is to move the decimal point two places to the right.

How to turn a decimal into a percent? – examples

It is possible to do with your calculators, but here are examples of conversion decimal fractions and decimal numbers into percent without using a calculator.

\frac{3}{4} = \frac{3\cdot 25}{4\cdot 25} = \frac{75}{100} = 75 \%

0.3 = \frac{0.3\cdot 100}{100} = \frac{30}{100} = 30 \%

Except by widening (or shortening) fractions so that their denominator equals the number 100, fractions can also be converted into percentages by first writing them in the form of a decimal number and then writing the decimal record of the fraction in the form of a percent.

\frac{1}{4} = 1:4 = 0.25 = 25 \%

If you need to convert decimal to hexadecimal, our converter can help you.

Turn a number to a percent and a percent to a number

Here is an example of how you can turn one decimal number to percent and a percent to a decimal number without using calculator. You just need to multiply decimal number by 100 and add a percent sign %:

3.45 = 3.45\cdot 100 = 345 \%

If you want to convert a percent to a decimal number, simply divide it by 100.

345 = \frac{345}{100} = 3.45

Or use our decimal to percent converter to do it for you quickly.


1. How to convert 20 percent to decimal?

20 = \frac{20}{100} = 0.2

2. How to change 34.55 percent to a decimal?

34.55 = \frac{34.55}{100} = 0.3455

3. How to convert 40 percent to a decimal?

40 = \frac{40}{100} = 0.4