Ratio Calculator & Proportional Split
Simplify a whole-number ratio and divide a chosen total between its two parts.
Your inputs
Use consistent units and periods. Defaults are examples.
Your result
Check the assumptions below before relying on a result.
Formula and method
Divide both ratio parts by their greatest common divisor. First allocation = total × first ÷ (first + second); second allocation = total − first allocation.
Worked example
120:80 simplifies to 3:2. Splitting 1,000 in that ratio allocates 600 to the first part and 400 to the second; the first share is 60%.
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