How it works
A ratio compares two quantities. Equivalent ratios satisfy A:B = C:D (cross-multiply). You can also simplify A:B or scale it up or down.
A:B = C:D → A×D = B×C
When to use
Use A:B = C:D with any three known values. Switch to Simplify or Scale for reducing and enlarging ratios.
How to use this tool
- Enter your values in the fields above.
- Review the formula and any mode options for your problem.
- Read the result and the step-by-step solution.
Use A:B = C:D with any three known values. Switch to Simplify or Scale for reducing and enlarging ratios.
Frequently asked questions
- What is the Ratio Calculator?
- A ratio compares two quantities. Equivalent ratios satisfy A:B = C:D (cross-multiply). You can also simplify A:B or scale it up or down.
- How do I use the Ratio Calculator?
- Enter the required values, then calculate. The Ratio Calculator shows results, formulas, and step-by-step work when available. No account is required.
- What formula does the Ratio Calculator use?
- A:B = C:D → A×D = B×C
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