⚖️ Ratio Calculator
Simplify a ratio to its lowest terms, or solve a proportion (A:B = C:D) for a missing value.
Mode
Your Result
Simplified Ratio
2 : 3
Decimal Equivalent
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Full Proportion
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How the Ratio Calculator Works
A ratio compares two quantities. Simplifying a ratio reduces it to its lowest terms using the greatest common divisor (GCD), while solving a proportion finds a missing value that keeps two ratios equal.
Formulas
Simplify: A:B → (A ÷ GCD) : (B ÷ GCD)
Solve proportion A:B = C:D
If solving for D: D = (B × C) / A
If solving for C: C = (A × D) / B
Solve proportion A:B = C:D
If solving for D: D = (B × C) / A
If solving for C: C = (A × D) / B
Frequently Asked Questions
How do I simplify a ratio?
Divide both numbers in the ratio by their greatest common divisor (GCD). For example, 8:12 simplifies to 2:3 because the GCD of 8 and 12 is 4.
What is cross multiplication?
Cross multiplication is used to solve proportions of the form A:B = C:D. Multiplying A×D and B×C gives equal products, which lets you solve for any single unknown value.
Can ratios include decimals?
Yes, this calculator accepts decimal values for both simplifying and solving proportions.