Purpose: Simplify a ratio to its lowest terms, or solve a proportion by leaving one value blank.
Simplify a ratio
Solve proportion A : B = C : ?
Ratio Calculator
The Ratio Calculator simplifies ratios, solves proportions for a missing value, and scales a ratio up or down - useful for recipes, mixing, maps, and model scales.
Simplify and solve
Enter a ratio like 1024:768 and it reduces to 4:3 by dividing both sides by their greatest common divisor. Enter a proportion with one unknown - such as 3:4 = 9:? - and it solves for the missing term by cross-multiplication (here, ? = 12).
Everyday scaling
Scaling ratios is what you do when doubling a recipe, mixing fuel and oil, converting a map distance to real distance, or resizing an image while keeping its aspect ratio. Keep the ratio constant and change one quantity, and the calculator returns the matching value.
Frequently Asked Questions
How does it simplify a ratio?
It divides both parts of the ratio by their greatest common divisor, so 1024:768 becomes 4:3.
How do I solve a proportion for the missing number?
Enter three of the four terms in the form a:b = c:d and the calculator cross-multiplies to find the unknown.
Can it handle ratios with three parts?
Yes, it can simplify and scale ratios such as 2:3:5 as well as simple two-part ratios.
Is this useful for keeping image aspect ratio?
Yes. Enter the original width:height and one new dimension to find the other while preserving the aspect ratio.
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