Simplify ratios like 12:18:30 to their simplest form, see each part as a share of the total, or solve A:B = C:D for the missing value.
About this tool
Simplify ratios, solve A:B = C:D and scale a ratio up or down.
How to use Ratio Calculator
- Choose Simplify a ratio or Solve A:B = C:D.
- Enter the ratio, or A, B and C.
- Read the simplified ratio or the value of D.
Worked example
A recipe for 3 people uses 4 cups of flour. For 15 people, solve 3:4 = 15:D to get 20 cups.
How is a ratio simplified?
Every part is divided by their greatest common factor. 12:18:30 divides by 6 to give 2:3:5.
Can a ratio have decimals?
Yes. Decimals are scaled up to whole numbers before simplifying.
- Ratio Calculator — Simplify ratios, solve A:B = C:D and scale a ratio up or down.
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