Ratio Calculator
Simplify a ratio of two or three numbers to its lowest terms, useful for recipes, mixing solutions or scaling drawings.
Your results
Calculation breakdown
- Simplified ratio
- Each part ÷ GCD of all parts
Worked example
A concrete mix of 4 parts cement to 6 parts sand simplifies to 2 : 3.
Assumptions
- Leave the third field at 0 to work with a two-part ratio.
- Decimal inputs are rounded to whole numbers before simplifying.
How this calculator works
This calculator simplifies a ratio of up to three numbers to its lowest whole-number terms by dividing each part by their greatest common divisor. It's useful for scaling recipes, mixing concrete or comparing quantities.
Frequently asked questions
Can I simplify a ratio with three parts?
Yes, enter a third value and the calculator will simplify all three numbers together using their combined greatest common divisor.
What if one value is zero?
A zero value is treated literally, so the simplified ratio will also show zero in that position.
Does it work with decimals?
The calculator is designed for whole numbers; decimal inputs are rounded before simplifying.
Editorial review and responsibility
Reviewed by the CalcAussie editorial team on 21 September 2026. Review scope: Method, Australian terminology, material assumptions, source links and user-facing limitations.
Calculator results remain estimates based on the figures entered. Check material decisions against current official information and report a suspected error so it can be reproduced and corrected.