School
Ratio Calculator
A ratio utility that simplifies A:B to lowest terms, scales parts to a chosen total, and solves for a missing part when one side and the ratio are known. Useful for recipes, concrete mixes, and classroom math. Not a statistical odds model.
Frequently asked questions
How do you simplify a ratio?
Divide both parts by their greatest common divisor. 12:18 simplifies to 2:3.
How do I scale a ratio to a total?
Add the parts, divide the desired total by that sum, then multiply each part by that factor.
Can ratios have decimals?
Yes. The tool accepts decimals and can still simplify by scaling to whole numbers when possible.
What is a part-to-part vs part-to-whole ratio?
Part-to-part compares two groups (3:5). Part-to-whole compares one group to the total (3:8).
Is a ratio the same as a fraction?
A ratio A:B can be written as the fraction A/B, but ratios often keep both parts visible for mixing.
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