Can one part be zero?
Yes. A ratio such as 0:3 is valid; 0:0 has no defined relative size.
Ratio Calculator
Reduce two non-negative quantities to their simplest whole-number ratio.
Try the calculator
Adjust the values below to get a clear estimate.
Scale then reduce
Both parts are scaled to a common power of ten, rounded to integer units, and divided by their greatest common divisor. The reduced terms retain the original proportion.
a:b → (a × scale / gcd):(b × scale / gcd)Worked example
Reduce a 12 to 18 comparison
Inputs: firstPart: 12 · secondPart: 18
Illustrative result: 2:3
Both terms divide evenly by 6, so the reduced ratio has two parts for every three parts.
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Frequently asked questions
How precise can decimal inputs be?
Up to six decimal places are supported to keep scaling within safe integer arithmetic.