How do you convert a part-to-whole ratio to a fraction?

To convert a part-to-whole ratio directly to a fraction, simply place the first number (part) over the second number (whole). For example, 3:8 becomes the fraction 3/8. Then reduce to lowest terms by dividing by the GCF.

What is a ratio in simplest form?

A ratio is in simplest form when the greatest common factor (GCF) of both numbers is 1, meaning no whole number other than 1 divides both evenly. For example, 6:10 simplifies to 3:5 because the GCF of 6 and 10 is 2.

Can a ratio have three parts?

Yes, a ratio can have three or more parts such as A:B:C. To convert to fractions, add all parts to get the total denominator, then write each part as a fraction over that total. Reduce each fraction to lowest terms.

Ratio to Fraction Calculator

Ratio to Fraction Calculator | Convert Ratios to Fractions Free

Ratio to Fraction Calculator

Convert any ratio to a fraction instantly. Supports part-to-part and part-to-whole ratios with step-by-step solutions.

Convert Ratio to Fraction

Select Ratio Type:

Part-to-Part Part-to-Whole

A : B

Part	Fraction (Unreduced)	Fraction (Simplified)

Ratio to Fraction Reference Table

Ratio to fraction conversion reference shows common ratios and their equivalent simplified fractions.

Ratio (A:B)	Type	Fraction A	Fraction B
1 : 1	Part-to-Part	1/2	1/2
1 : 2	Part-to-Part	1/3	2/3
1 : 3	Part-to-Part	1/4	3/4
1 : 4	Part-to-Part	1/5	4/5
2 : 3	Part-to-Part	2/5	3/5
3 : 5	Part-to-Part	3/8	5/8
1 : 3	Part-to-Whole	1/3	—
3 : 4	Part-to-Whole	3/4	—
5 : 8	Part-to-Whole	5/8	—
7 : 10	Part-to-Whole	7/10	—

How to Convert a Ratio to a Fraction

Ratio to fraction conversion follows a clear process depending on whether you have a part-to-part or part-to-whole ratio. Understanding which type you have is the essential first step.

Converting Part-to-Part Ratios

A part-to-part ratio compares two quantities within a whole. To convert ratio A:B to fractions, first find the total by adding A and B. The total becomes the denominator for both fractions. Part A becomes A/(A+B) and part B becomes B/(A+B). Then reduce each fraction by dividing numerator and denominator by their greatest common factor (GCF).

Example: Ratio 6:8 gives a total of 14. Part A = 6/14 = 3/7. Part B = 8/14 = 4/7.

Converting Part-to-Whole Ratios

A part-to-whole ratio already tells you the fraction directly. Ratio A:Total converts to fraction A/Total. Simply reduce the fraction to lowest terms using the GCF of A and Total.

Example: Ratio 6:14 becomes fraction 6/14 = 3/7 after dividing both by GCF of 2.

How to Find the Greatest Common Factor

The GCF is the largest number that divides both the numerator and denominator evenly. List all factors of each number and identify the largest one they share. Divide both by the GCF to get the fraction in lowest terms. If the GCF is 1, the fraction is already fully simplified.

When to Use Each Ratio Type

Choosing the correct ratio type ensures your fraction conversion is accurate and meaningful in context.

Use a part-to-part ratio when comparing two groups within a larger whole, such as boys to girls in a class, or red marbles to blue marbles in a bag. Neither part represents the total.

Use a part-to-whole ratio when one value represents the total and the other is a subset, such as 3 wins out of 10 games played. The ratio converts directly to a fraction representing a share of the total.

Three-part ratios like A:B:C are always part-to-part. Each part converts to a fraction with denominator A+B+C.

Frequently Asked Questions

To convert a ratio A:B to a fraction, add A and B to get the total denominator, then write each part over that total. For example, ratio 3:1 becomes 3/4 and 1/4. Reduce each fraction by dividing by the greatest common factor.

A part-to-part ratio compares two parts of a whole to each other, such as 3:5 (apples to oranges). A part-to-whole ratio compares one part to the entire group, such as 3:8 (apples out of all fruit). Part-to-whole ratios convert directly to fractions while part-to-part ratios require adding both parts first.

To simplify a fraction obtained from a ratio, find the greatest common factor (GCF) of the numerator and denominator. Divide both by the GCF. The result is the fraction in its simplest form. For example, 6/14 simplifies to 3/7 because the GCF of 6 and 14 is 2.

Yes. For a three-part ratio A:B:C, the total is A+B+C. Each part becomes a fraction with that total as the denominator: A/(A+B+C), B/(A+B+C), and C/(A+B+C). Reduce each fraction to its lowest terms using the GCF.

A ratio and a fraction are related but not identical. A ratio compares two quantities (3:5), while a fraction represents a part of a whole (3/8). A part-to-whole ratio can be written directly as a fraction. A part-to-part ratio must be converted using the sum of both parts as the denominator.