Ratio Calculator
Simplify ratios, convert to fractions, percentages and decimals instantly with our free online ratio calculator.
How to Use This Calculator
- Enter Value A and Value B into the input fields.
- Click Calculate to simplify the ratio and see all conversions.
- View the simplified ratio (lowest terms), the GCD, each value as a percentage of the total, and the decimal equivalent.
Formula
A ratio a : b is simplified by dividing both values by their Greatest Common Divisor (GCD).
Percentage of A = a / (a + b) × 100%
Percentage of B = b / (a + b) × 100%
Decimal = a / b
Examples
Mixing Paint
A ratio of 12:8 paint to thinner simplifies to 3:2 — for every 3 parts paint, use 2 parts thinner.
Recipe Scaling
A recipe calls for flour and sugar in a 5:3 ratio. If you have 500g flour, you need 300g sugar.
Classroom Ratio
18 boys and 12 girls simplifies to a 3:2 ratio of boys to girls (GCD = 6).
Frequently Asked Questions
What is a ratio?
A ratio is a comparison of two quantities that shows how many times one value contains or is contained within the other. It is commonly written as a : b or as a fraction a/b.
How do you simplify a ratio?
Find the Greatest Common Divisor (GCD) of both numbers and divide each by the GCD. For example, the ratio 12:8 has a GCD of 4, so dividing both by 4 gives 3:2.
What is the difference between a ratio and a fraction?
A fraction represents a part of a whole (numerator/denominator), while a ratio compares two separate quantities (a:b). However, both can be expressed as decimals and percentages.
Can a ratio have more than two terms?
Yes. A ratio can compare three or more values, such as 2:3:5, commonly used in recipes and ingredient mixing.