What is the ratio of 1 2

A ratio is a mathematical term to show the relationship between two numbers of the same kind. This is a good calculator for understanding the basics of ratios, we also provide links to related calculators with supporting tutorials to help you build your knowledge of ratios and check your own calculations and answers to ensure you understand how to calculate ratios correctly. We have provided a video which covers the basics of ratios below, this is designed for those new to the topic and those new to iCalculator™ who may not be familiar with the free calculators and tutorials we provide.

Use this calculator to simplyfy a ratio and express it in terms of 1:n or click on the options below to complete alternate math calculations for ratios:

Please leave a rating for this ratio calculator, it helps us to keep this calculator and our other calculators free for all to use across the globe.

Ratios can be expressed in several ways, this ratio calculator calculates ratios and displays the results using various ratio expressions as shown below:

1. The ratio of A to B
2. A:B
3. Form 1:n and n:1
4. A is to B as C is to D

Ratio calculations can be saved to a table using the Equivalent Ratio Calculator, this is useful when you need to calculate several ratios and then compare the ratios on completion

How to add, subtract, multiply and divide ratios

Now that we have covered the basics of how ratios can be expressed, you can review the additional information on ratio expression or jump straight to the ratio tutorials covering basic math functions with ratios:

How can Ratios be expressed?

Ratios can be expressed in a numbers of ways, as a decimal, a fraction as a related comparison or as is more commonly seen a percentage. for example a ratio of 1 to 2 can be expressed as:

1. 1-2 is a ratio expressed in using a hyphen, whilst this is quite commonly used it should be avoided as the hyphen also represents the minus sign in math and can be confusing in long algorithms or if using computer code or computers to process a math calculation
2. 1:2 is a ratio expressed in typical math format using a colon
3. 1 to 2 is a ratio expressed in written words
4. 1 per 2 is a ratio expressed in written words
5. 0.5 is a ratio expressed as a decimal number
6. 50% is a ratio expressed as a percentage
7. ½is a ratio expressed as a fraction

Learn more about Ratios or try one of our popular ratio calculators, a selection of which are provided below.

Ratio of 1 to 3

home / math / ratio calculator

Please provide any three values below to calculate the fourth in the ratio A:B = C:D.

Ratio Scaling Calculator

What is Ratio?

A ratio is a quantitative relationship between two numbers that describe how many times one value can contain another. Applications of ratios are fairly ubiquitous, and the concept of ratios is quite intuitive. This could likely be demonstrated by giving a child half as many cookies as his sister. While the child may not be able to voice the injustice using ratios, the raucous protestations that would most likely ensue should make it immediately obvious that he is well aware he has received 1:2 as many cookies as his sister, conceptually, if not mathematically.

As shown above, ratios are often expressed as two numbers separated by a colon. They can also be written as "1 to 2" or as a fraction ½. The ratio represents the number that needs to be multiplied by the denominator in order to yield the numerator. In this case, ½. This is clearer if the first number is larger than the second, i.e. with the ratio 2:1, 2 can contain 1, 2 times. It is also possible to have ratios that have more than two terms.

Ratios are common in many daily applications including: aspect ratios for screens, describing maps and models as a scaled-down version of their actual size, in baking and cooking, when discussing the odds of something occurring, or to describe rates, such as in finance. If, for example, a person wanted to make 5 cakes, each of which required a 1:2:3 ratio of butter:sugar:flour, and wanted to determine the total amount of butter, sugar, and flour that is necessary, it would be simple to compute given the ratio. Increasing the ratio by five times yields a 5:10:15 ratio, and this can be multiplied by whatever the actual amount of sugar, flour, and butter are used in the actual cake recipe.

Typical Aspect Ratios and Sizes of Screens and Videos

The aspect ratio is the ratio of a geometric shape's sizes in different dimensions. In the case of a rectangle, the aspect ratio is that of its width to its height. Although aspect ratios are widely used in applications such as tire sizing, paper sizing, and standard photographic print sizes, some of the most frequent uses of aspect ratios involve computer screen dimensions, mobile phone screens, and video sizes. As such, below is a list of typical computer screen/video resolutions and aspect ratios.

Get a Widget for this Calculator

Use this calculator to simplify ratios of the form A : B. A or B can be whole numbers, integers, decimal numbers, fractions or mixed numbers. They can be different types, for example, one fraction and one decimal. The ratio values can be positive or negative.

This calculator simplifies ratios by converting all values to whole numbers then reducing the whole numbers to lowest terms using the greatest common factor (GCF). The full solution shows all work and the steps to get a ratio into simplest form.

What is a Ratio?

A ratio is a comparison of the value of two numbers. The ratio A : B is read as "A to B" and describes the relative proportion of two amounts.

How to Simplify a Ratio A : B when A and B are both whole numbers

• List the factors of A
• List the factors of B
• Find the greatest common factor of A and B, GCF(A, B)
• Divide A and B each by the GCF
• Use the whole number results to rewrite the ratio in simplest form

If the GCF = 1 then the ratio is already in simplest form.

How to Simplify a Ratio A : B when A and B are not whole numbers, in this order

• If A or B are mixed numbers convert mixed numbers to improper fractions
• If A or B are decimal numbers multiply both values by the same factor of 10 that will eliminate all decimal places
• If one value is a fraction and the other a whole number, reduce the fraction to a whole number if you can or turn the whole number into a fraction by giving it a denominator of 1.
• If both A and B are fractions and have like denominators, multiply both fractions by the denominator to eliminate it and you are left with two whole numbers
• If both A and B are fractions and have unlike denominators, find the LCD(A, B) and rewrite the fractions with the LCD as the denominator. Multiply both fractions by the denominator to eliminate it and you are left with two whole numbers
• If both A and B are whole numbers, Find the greatest common factor of A and B, GCF(A, B), and divide A and B each by the GCF

Example: Simplify the ratio 6 : 10

• The factors of 6 are: 1, 2, 3, 6
• The factors of 10 are: 1, 2, 5, 10
• Then the greatest common factor of 6 and 10 is 2
• Divide both terms by 2
• 6 ÷ 2 = 3
• 10 ÷ 2 = 5
• Rewrite the ratio using the results. The simplified ratio is 3 : 5.
• 6 : 10 = 3 : 5 in simplest form

Example: Simplify the ratio 8 : 36

• The factors of 8 are: 1, 2, 4, 8
• The factors of 36 are: 1, 2, 3, 4, 6, 9, 12, 18, 36
• The greatest common factor of 8 and 36 is 4
• Divide both terms by 4
• 8 ÷ 4 = 2
• 36 ÷ 4 = 9
• Rewrite the ratio using the results. The simplified ratio is 2 : 9.
• 8 : 36 = 2 : 9 in simplest form

Example: Simplify the ratio 3 : 8

• The factors of 3 are 1, 3
• The factors of 8 are: 1, 2, 4, 8
• The greatest common factor of 3 and 8 is 1
• Divide both terms by 1
• 3 ÷ 1 = 3
• 8 ÷ 1 = 8
• Rewrite the ratio using the results. The ratio 3 : 8 is already simplified.

You can conclude that if the greatest common factor is 1 then the ratio is already in simplest form.

Related Calculators

To compare multiple ratios see our Ratio Calculator.

To simplify a fraction into a reduced fraction or mixed number use our Simplifying Fractions Calculator.