How to use this calculator
Enter A:B and a positive multiplier k. Multiplying both terms by k gives A×k:B×k. This changes the quantities while preserving their relative relationship. The calculation table includes several further multiples of the original ratio.
Formula
A : B → (A × k) : (B × k)
Worked example
For 2:3 with a multiplier of 4, the equivalent ratio is 8:12. The original and scaled ratios both reduce to 2:3. With k = 0.5, the result is 1:1.5, which is still equivalent.
Assumptions and limitations
A and B must be nonnegative and not both zero. The multiplier must be positive; multiplying both sides by zero destroys the relationship. Scaling is not the same as adding the same amount to each side.
Frequently asked questions
Why does adding the same amount not work?
Adding 2 to both sides of 2:3 produces 4:5, a different relationship. To preserve a ratio, multiply or divide both terms by the same nonzero factor.
How precise are the results?
Finite decimal inputs are converted to fractions and reduced with integer arithmetic. Fractions and reduced ratios are exact within the input limits. Decimal displays use up to six places, or scientific notation for tiny nonzero results.
Does 2:3 mean the first part is two thirds of the total?
No. In a part-to-part ratio of 2:3, the total has five parts. The first share is 2/5 (40%) and the second is 3/5 (60%).
Exact reduction; decimal displays may be rounded.