General
Ratio Calculator
Simplify ratios, scale proportions, find equivalent ratios, and convert to percentages. Includes a cooking mode for recipe scaling.
Supports 2+ parts: 3:2, 6:4:2, etc.
Enter a ratio and click Calculate
How is this calculated?
Simplify: divide all parts by GCD of all parts
Scale: multiply all parts by scale factor
Equivalent: multiply all parts by 2, 3, 4, ...
To %: part / sum(all parts) × 100FAQ
Frequently asked questions about ratios
How do I simplify a ratio?
Divide all parts of the ratio by their Greatest Common Divisor (GCD). For example, 12:8 — GCD is 4, so 12÷4 : 8÷4 = 3:2. The calculator finds the GCD automatically.
How do I scale a ratio?
Multiply all parts by the same factor. For example, to scale 2:3 to have the first part equal 10, multiply both by 5: 10:15. Useful for recipe scaling.
How do I convert a ratio to percentage?
Add all parts, then divide each part by the total and multiply by 100. For 3:2, total is 5, so 3/5×100 = 60% and 2/5×100 = 40%.
What is an equivalent ratio?
Ratios that represent the same proportion. 2:3, 4:6, and 6:9 are all equivalent because they simplify to 2:3. Multiply or divide all parts by the same number.
How do I use ratios for recipe scaling?
Express your recipe ingredient amounts as a ratio. To scale, find what multiplier gets one ingredient to your desired amount, then apply that multiplier to all ingredients.
Is this ratio calculator free?
Yes, completely free with no sign-up required. All calculations run in your browser — your data stays on your device and is never sent to any server.