Ratio Calculator
Simplify a ratio and solve missing terms in proportional ratios.
About this calculator
The Ratio Calculator on NumberCals is a free, mobile-friendly tool for anyone needing to simplify a ratio and solve missing terms in proportional ratios. Enter your values in the form below and the result is computed instantly — no sign-up, no installation, no waiting.
Formula used
a:b = c:d => d = b·c / a
What you'll need
- A (e.g. 12)
- B (e.g. 18)
- C (optional, for proportion) (e.g. 30)
What you'll get
- Simplified Ratio
- Missing D (when C given)
Formula
a:b = c:d => d = b·c / a
Result
Frequently Asked Questions
What's the difference between ratio and proportion? +
A ratio compares two quantities. A proportion states that two ratios are equal.
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