Ratio Calculator
Simplify a ratio, divide a total into proportional parts or solve a missing corresponding quantity. A labelled visual shows the relative parts without relying on colour alone.
Your result
How the calculation works
Simplification multiplies each accepted decimal by 10^6 and divides the integer pair by their greatest common divisor. To split total T, first = T × A/(A+B), second = T × B/(A+B). For A:B = C:D, D = C × B/A.
Worked example
12:8 simplifies to 3:2. Dividing 100 in that ratio gives 60 and 40. If A=12 corresponds to B=8 and a new first quantity is 30, its corresponding second quantity is 20.
Assumptions and limitations
A and B must be positive comparable quantities. Decimal simplification supports at most six decimal places and uses exact integer reduction. Scaling outputs use browser floating-point arithmetic. Convert differing units before entering them.
For a 16:9 aspect ratio, enter A=16, B=9; use missing mode with C as the new width. For a recipe ratio, use one consistent mass or volume unit. A zero total can be split, but zero ratio terms are outside this model.
Method reviewed 2026-10-08. Calculation standards · Report an issue