Ratio Calculator
Solve missing values in proportions and simplify any ratio.
π Updated October 13, 2026
About the Ratio Calculator
Solve it in seconds with the Ratio Calculator. Solve missing values in proportions and simplify any ratio. Accurate, instant and free β no signup, no app install. Students also reach for the Percentage Calculator and Scientific Calculator.
How to use this calculator
- Enter your numbers in the fields above.
- Results update instantly β no button to press, no page reload.
- Adjust the inputs to compare scenarios with the Ratio Calculator.
Keep exploring: Percentage Calculator Β· Basic Calculator Β· Date Difference Calculator Β· Scientific Calculator
Frequently asked questions
How do ratios work?
a:b = c:d solves to d = bΓcΓ·a β cross multiplication.
Can it simplify?
Yes β any ratio reduces to lowest terms automatically.
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