Ratio Calculator
Simplify a ratio, or solve for the missing fourth value in a proportion.
Overview
Ratios show up in two common problems: reducing a ratio like 24:36 to its simplest form (2:3), and scaling a known ratio to find a missing value in an equivalent proportion, like finding how much of ingredient B is needed if a recipe ratio of A:B is scaled up. This tool covers both without needing to work the greatest common divisor or cross-multiplication out by hand.
Examples & Sample Data
Simplify
24:36
2:3
Solve proportion
2:3 = 10:?
15
How It Works
- Choose a mode: Simplify a ratio, or Solve a proportion.
- Enter the known values.
- The result appears instantly.
Common Use Cases
Recipe scaling
Scale a recipe ratio up or down while keeping ingredient proportions the same.
Mixing ratios
Solve for the correct amount of a second component given a known mixing ratio, like paint or concrete.
Tips & Best Practices
- A ratio simplifies the same way a fraction does — both sides are divided by their greatest common divisor.
Frequently Asked Questions
No. Every calculation runs locally in your browser.
The Simplify mode expects whole numbers, since a ratio in lowest terms is conventionally expressed with whole numbers. The Solve-a-proportion mode accepts decimals for all three known values.
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