Simplify ratios, solve proportions (find missing value), and scale ratios up or down.
Enter 3 values, leave one blank (?) to find it. A:B = C:D
This tool simplifies ratios to their lowest terms and solves for missing values in proportional relationships. It's useful for cooking measurement scaling, financial ratios, map scales, and any comparison of two or more quantities.
A ratio a:b is simplified by dividing both values by their greatest common factor. For solving proportions (a:b = c:d), cross-multiplication is used: a × d = b × c, allowing you to solve for any single unknown value.
Enter your ratio values, or enter a proportion with one unknown value, and the calculator simplifies the ratio or solves for the missing number.
Example 1: The ratio 8:12 simplifies to 2:3 by dividing both numbers by their GCF of 4.
Example 2: If 2:3 = 10:x, cross-multiplying gives 2x = 30, so x = 15.
What's the difference between a ratio and a fraction? A ratio compares two or more quantities to each other (like 3:1), while a fraction represents a part of a single whole — though ratios can often be expressed as fractions when comparing exactly two quantities.
Why do we simplify ratios? Simplifying makes ratios easier to understand and compare, expressing the same proportional relationship using the smallest possible whole numbers.
How are ratios used in cooking? Recipe scaling relies on ratios to maintain proportions when adjusting serving sizes — for example, doubling a recipe means doubling every ingredient while keeping their ratios to each other constant.
What is a proportion? A proportion is an equation stating that two ratios are equal (like 2:3 = 4:6), which is useful for solving problems where one quantity is known and a corresponding scaled quantity needs to be found.
Can ratios compare more than two quantities? Yes, ratios can express relationships among three or more quantities (like 2:3:5), commonly used in mixing recipes, concrete ratios, or financial allocations across multiple categories.